Cross-connect method and apparatus

ABSTRACT

A remotely controlled cross-connection switching matrix, particularly suited for telephone systems, has a jumper pin picker and placement mechanism selectively movable along each of three axes under the control of a single drive motor translating a single drive cable over a series of pulleys. Movement along the selected axis is effected by braking movement along the other two axes. The system provides a “soft dial tone” to prospective telephone subscribers&#39; premises having cable pairs permanently connected to the matrix. The cable pair for the calling prospective subscriber is automatically identified at the matrix in response to an off-hook status for that prospective subscriber, and the cable pair identification data is automatically transmitted to the telephone business office. Stored information at the business office for the premises of the identified cable pair is automatically displayed for the telephone company representative responding to a request for service by the calling prospective subscriber. The matrix also permits remote selective connection of unused telephone lines to a test bus connected between the matrix and the central office, thereby permitting automatic, remotely controlled testing of those lines. Improved security of the facility containing the matrix is provided by a feature permitting remote control over the facility door lock.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.08/408,831, filed Mar. 20, 1995 and entitled “Cross Connect Method andApparatus”, now U.S. Pat. No. 6,031,349, which is a continuation-in-partof U.S. patent application Ser. No. 08/111,770, filed Aug. 25, 1993 andentitled “Cross Connect System”, now U.S. Pat. No. 5,456,608. The entiredisclosures in the above-identified patent applications are incorporatedherein by this reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates generally to automatically controlledmatrix switching systems and, more particularly, to methods andapparatus for automatically and selectively providing cross-connectswitching functions in a telephone system.

2. Discussion of the Prior Art

In the above-noted U.S. patent application Ser. No. 08/111,770, there isdescribed and illustrated a remotely controlled cross-connect matrixarrangement having particular but not limited application in selectivelyconnecting multiple telephone subscriber pairs to multiple telephonesystem or central office lines. That system utilizes a unique pick andplace mechanism for automatically inserting jumper pins at desiredmatrix locations to provide service for individual subscribers. Althoughthat pick and place mechanism is effective to perform its intendedfunctions, the mechanism requires three separate motors to position thejumper pin holder along three respective axes to insert and/or remove ajumper pin. The three motor approach is costly and results in a degreeof complexity that has now been found to be unnecessary.

It has also been found that the cross-connect matrix approach of theabove-referenced prior patent application is ideally suited forperforming other important telephone system functions. In particular,telephone facilities that are typically utilized in providing telephoneservice to a customer include a telephone number, a central office linetermination, a cross-connection via a mainframe or cross-connection unitto a cable pair extending via several types of outside plant facilitiesto a terminal near the customer's home or business, and wiring from theterminal into the home/business and to the telephone. Each of thesecomponents must have its own identification code to distinguish it fromamong thousands of identical components that may or may not be inservice. These codes for the various components are specified on aservice installation order to inform technicians exactly whichcomponents to connect together to provide the overall circuit for thecustomer. When all of the components have been properly connected andthe line tested, the customer can plug his/her telephone into the lineand utilize the service.

Telephone companies typically issue orders to disconnect each of thesefacility connections all along the circuit when a customer moves or theservice is otherwise disconnected. Individual components are thenreturned to the assignment availability list for re-use in response to asubsequent request for service. In recent years, increases in technicallabor costs have caused telephone companies to attempt a variety ofschemes to reduce that cost by leaving many of the component connectionsintact when a customer disconnects service, and then using the sameconnected components for the next customer to occupy the formercustomer's premises. This method of operation is known by various namesthroughout the industry such as:

(a) Dedicated Outside Plant (DOP). In this approach the cable pairremains connected from the mainframe in the central office to theserving area interface (i.e., the cross-connection point), to a terminalat the customer's location and on into the home/business. This techniqueis sometimes called “connect-thru”.

(b) Dedicated Inside Plant (DIP). The office equipment line terminationremains connected to the cable pair that served the former customer.

(c) Flow Through. This term is used when service is established for anew customer by reusing all former facilities and no field work orcentral office work is required.

(d) Soft Dial Tone. This is a recent innovation made possible by storedprogram controlled switching systems permitting programming of theoffice equipment terminal that had been used by the previous occupant ina manner to permit the incoming new customer to contact only thetelephone business office and emergency 911 even though service has notbeen officially established at the facility.

All of the foregoing methods require that the facilities to thecustomer's location be left in place from the customer's connectionblock in the home/business to the office equipment terminal in thecentral office. There are tremendous labor savings inherent in thesemethods of operation. However, as telephone companies have becomeinvolved in these processes they have found that there are seriousdrawbacks and problems not readily apparent in initial plans. Some ofthese, for the above-described methods include:

1. Dedicated Outside Plant (DOP). The greatest obstacle in DOP is lossof flexibility in utilizing capital investment. Outside plant cablefacilities are designed using a multiplying scheme to provide maximumflexibility in utilizing cable pairs. When these pairs are leftconnected to the central office mainframe, they are unavailable forchanges and rearrangements necessary to fully utilize capitalinvestment. The result is an increase in capital requirements for newfacilities. A feeder cable pair from a serving area interface to thecentral office is very expensive; when dedicated to a non-working line,it is not available for use by paying customers, resulting in a waste ofcapital investment.

2. Dedicated Inside Plant (DIP). There is a tremendous capital penaltyinvolved in leaving the central office equipment connected to theoutside cable pair. Central office administrative spares (i.e.,operating spares) are designed and provided from specific formulae basedon a precise percentage of available lines being idle at any given time.When these office equipment terminals are left connected to the outsideplant cable pair, they are unavailable for use as administrative sparesand can be assigned only when a customer occupies the dwelling orbusiness where the cable pair is terminated. At any given time there areapproximately ten percent of the available lines idle or disconnected inthe normal course of business (i.e., people moving in and out of thecity, people moving from one home or business to another, new customers,present customers disconnecting service, customers adding lines, etc.).This activity is called “the float” or “churn” in the telephoneindustry. It is an expensive but necessary part of the telephonebusiness. The average central office line termination currently costsapproximately one hundred and fifteen dollars to one hundred and fiftydollars each. When one considers the thousands of lines involved in theDIP method, it becomes apparent that this method is very expensive froma capital utilization point of view. Considerable effort has beenexpended throughout the industry to resolve the labor versus capitalcosts impasse. Many companies have indicated that the economic impact ofidle capital investment, while having to purchase new terminations fornew service, outweighs the cost of making the connections manually.

3. Flow Through. When a decision to stop or not provide DIP isimplemented, the “flow through” of service orders is stopped. This, ineffect, puts the service order process back where it was before thelabor saving plans were implemented, meaning that every service ordermust be manually processed to establish service. When one considers allthe different assignments and cross-connections involved, this obviouslyis a major problem. Even with fully dedicated outside plant (DOP) andinside plant (DIP), there is another serious obstacle to increasing thelabor saving “flow through” of service orders to establish telephoneservice. This is the problem of identification of the line serving thecustomer that is just moving in to occupy the premises. Many homes,particularly in rural areas, do not have precise addresses. Manyapartment buildings do not precisely identify the apartment location;rather, only the street address of the apartment building is listed, andsome carry only the street address plus the floor or story number. Thus,even if such a customer is properly connected through to the centraloffice equipment, the customer has no way of telling the business officethat service is desired, or precisely where he/she lives, or whatfacility is connected to the dwelling unit. In theory, these data shouldbe available from assignment records; however, if the addresses are notavailable, assignment records cannot locate the customer. In many cases,entire duplicate facility connections are assigned and sent to the fieldfor the technician to install because the original facility recordscannot be located. In order to solve a part of this problem, that is,notification to the business office that service is desired, the “softdial tone” technique was developed.

4. Soft Dial Tone. Many telephone companies found that simply leavingfacilities connected to the main frame still required the customer tofind a working telephone or pay telephone to call the business office toapply for service. The “Soft Dial Tone” technique was developed to solvethis problem. Under this technique, all facilities are left connectedfrom the customer to the switching machine. In addition, a telephonenumber is assigned and attached to the non-working line. This switchingmachine, as do all switching machines, has means to automaticallyidentify the telephone number that is attached to a particular telephonefacility. This is called “Automatic Number Identification” (ANI). The“soft dial tone” operation under this method proceeds in the followingmanner. When a customer moves into a dwelling unit that has been leftconnected through to the central office switch, he/she plugs in atelephone and receives a dial tone. The telephone number assigned tothat facility has been programmed in the switch software to restrict allcalls from that number except 911 or to the telephone company businessoffice number. When the customer calls the business office, assumingeverything has been perfectly recorded and all facilities have beenproperly connected, the customer gives the business office the addressof the dwelling unit. The service representative then calls anassignment bureau where all facilities are recorded and associated withthe dwelling units, and gives the assignor the house address of theapplicant. Assuming again that the customer can provide the exactaddress, apartment location, street numbers etc., the assignor candetermine from the records the probable cable facility that the customerhas called in on. He/she then has frame technicians “pull an ANI” on thecable pair to find the telephone number that is connected to that pair.If the ANI number matches the number in the records, the business officeinforms the customer that service will be established that day. Serviceorders are then issued to establish service using the facilities forthat dwelling unit; in addition, the temporary telephone number willhave to be changed or reprogrammed in the switching machine to permitnormal service. If all goes well and every piece of the facility wasleft as the records indicated, the service is established. Obviouslythis is better than the old method of simply leaving the cable pairsconnected to the central office mainframe, as the old method addsadditional labor back into the cost of providing the service. It istotally dependent, however, upon records and data that are notoriouslyinaccurate and, it requires coordination between four disparate workgroups. These groups are not co-located and may even be in differentcities. In addition, fully dedicated facilities for soft dial tonerequire the addition of another large capital investment to add atelephone number to a non-working line that produces no revenue. Thecapital cost of a single telephone number has been estimated between$300-$500. When one considers the thousands of lines that must betreated in this fashion every day of the year, the capital requirementsare obvious. Studies have shown that the capital cost of the facilitiesand telephone numbers involved, exceed the value of labor saved by useof this technique.

The foregoing description is applicable approximately twenty fivepercent of the time when dedicated facilities are utilized in both DIPand DOP techniques. Obviously, the “flow through” percentage is zero fornon-dedicated facilities. It must be recognized that the process takesplace every working day of the year in every central office in citiesand towns all over the world. The expense and labor involved in theseprocesses are enormous, and great amounts of thought, study and effortare expended in attempting to overcome specific obstacles and problemsto establishing “flow through” of orders for telephone service. Theseproblems include: idle outside plant capital investment resulting fromdedicated outside plant cable pairs; idle and “trapped investment” ofcentral office line terminations when DIP is used; and the inability toefficiently establish same day service when dedicated facilities are notutilized. In many cases the calling customer does not know the exactaddress or even the apartment number.

Where telephone numbers are not assigned to non-working lines because ofthe high capital expense, there is no ANI capability and therefore theassignment force is unable to identify the calling line even when theexact address is known and given to the business office. Without atelephone number, no electronic tests of the facility can be made toassure proper operation because all electronic test equipment connectsto the facility through the telephone number. This means that servicemust first be established, and then operational testing can be done. Inmany cases the facility is not suitable and all work must be done againand service activation is delayed.

The present invention solves these and other telephone serviceactivation problems and inefficiencies at a great capital and laborsavings to the telephone company. In addition, customer service isgreatly improved.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide a remotelycontrolled switching matrix having a low cost and efficient mechanismfor selectively removing jumper pins from and inserting jumper pins intomatrix connection holes.

It is another object of the present invention to provide a simpleremotely controlled mechanism for accurately positioning a matrix jumperpin along three orthogonally related axes of movement.

A further object of the invention is to provide an improved method fortranslating a pick and place mechanism for matrix jumper pins.

It is also an object of the present invention to provide a method ofeliminating the need for telephone companies to leave expensive centraloffice line terminations (DIP), telephone numbers and outside plantfeeder facilities (DOP) connected for lines not in service.

Yet another object of the invention is to provide “Soft Dial Tone” forprospective telephone customers in a manner that obviates the need forone-for-one central office terminations for each cable pair used and forone-for-one outside plant feeder cable pairs.

A still further object of the invention is to provide means for rapidlyidentifying the specific telephone line, from a multiplicity of lines,that is “offhook” (i.e., trying to use the telephone) and attempting tocall the telephone company business office.

A still further object of the invention is to eliminate the labor,expense and delays in activating customer service that are caused by theinability of the service representative to obtain facility assignmentand facility availability information. The present invention overcomesthis problem by providing means to automatically transmit to thetelephone company business office the total facility assignment of theline connected to the prospective customer's home or business from whicha call applying for service is made.

It is an object of the invention to provide a method for electronicallytesting both “soft dial tone” lines and non-working lines by uniquelyaccessing the telephone company mechanized loop testing equipment.

It is a further object of the invention to provide means for effectingsecurity for telephone buildings by controlling door entry control in aneconomical and efficient manner.

In accordance with one aspect of the present invention, a pick and placemechanism, suitable for use with the matrix assembly and jumper pinarrangement disclosed in prior U.S. patent application Ser. No.08/111,770, utilizes only a single stepping motor to translate themechanism along all three orthogonal axes. In the preferred embodiment asingle drive cable is driven by the single stepping motor and directedby a series of idler pulleys to travel horizontally, vertically andtransversely toward the matrix. Upper and lower horizontal transportblocks ride along respective upper and lower horizontally orientedsupport tubes. Idler pulleys for the drive cable are located on theseblocks, permitting the blocks to be moved along their respective supporttubes in response to disengagement of a normally engaged horizontalblock brake arrangement while vertical picker plate brakes remainengaged. A transport carriage similarly rides along respective left andright vertically oriented support tubes that are secured at their upperand lower ends to the upper and lower transport blocks, respectively.The vertical support tubes and vertical transport carriage thus movehorizontally with the horizontal support blocks. The drive cable isterminated at the vertical transport carriage to permit the carriage tomove vertically along the vertical support tubes when the horizontalblock brakes and picker plate pulley brake are engaged and the verticalcarriage brake is released.

A picker plate is mounted on the vertical carriage and is connected viaconnecting rods to a pulley rotatable about a horizontal axis orientedparallel to the horizontal support tubes. The ends of the drive cableare secured to this pulley. A brake mounted on the carriage enablesselective rotation of the picker plate pulley to effect controlledmovement of a jumper pin engaging picker toward and away from thematrix.

Movement of the picker in any one of the three orthogonally relateddirections (i.e., horizontally, vertically and depthwise) is achieved byreleasing the brakes for either the horizontal transport blocks, thevertical carriage or the picker plate pulley, respectively while theother brakes remain engaged. Precise horizontal and vertical braking isachieved by defining a series of longitudinally spaced slots in thehorizontal and vertical support tubes, the slot spacing corresponding tothe spacing between adjacent contact holes in the matrix. In thepreferred embodiment successive slots are offset circumferentially intwo rows to provide the requisite space between successive slots. Twosolenoids, one for each row of slots, are provided on the upperhorizontal transport block, and each has a plunger arm that isforcefully projected to be engaged in one of the slots when the solenoidis deenergized. When a solenoid is energized, its plunger arm isretracted from a slot and permits the horizontal transport block to movewith the drive cable. Similar solenoids are provided on the verticalcarriage. Thus by energizing braking solenoids for only one motiondirection at a time, the single drive cable and single drive motor areable to selectively move the picker in any one of the three directions.

In accordance with another aspect of the invention, prospectivetelephone subscriber locations having respective installed cable pairsare provided with “soft dial tone” using automatic control via thematrix. Plural prospective subscribers are connected in parallel by thematrix to central office battery and ground. When one of thoseprospective subscribers goes off hook, dial tone is provided via thematrix connection to the parallel-connected group of prospectivesubscribers. The system identifies the calling party with a uniquecontrol logic arrangement and connects his/her cable pair to a soft dialtone bus and disconnects the majority of parallel connections, therebypermitting the party to call only emergency 911 or the telephonebusiness office number. In order to eliminate degrading on the linecaused by the other paralleled prospective subscribers remaining bridgedto the calling party, a spare matrix pin is automatically inserted intothe matrix to jump the calling party's cable pair to a direct centraloffice line. This is done while the emergency or business office call isin progress. The calling prospective subscriber is thus, at leasttransiently, connected to the central office soft dial tone bus via twoparallel connections, namely the common access line and the newlyestablished direct central office line connection. The two speciallyconfigured jumper pin that had originally connected the callingprospective subscriber to the common access line in parallel with theother prospective subscribers are then moved to break the soft dial tonebus connection. This leaves the other prospective subscribers connectedto the soft dial tone connector bus and capable of receiving soft dialtone service while the calling prospective subscriber continues his/hercall to 911 or the telephone company business office.

In accordance with another aspect of the invention, means are providedto automatically select, from among hundreds of identical cable pairs,the specific cable pair used by the customer for his/her call to thebusiness office when applying for service when such call is made via the“soft dial tone” provisions of the present invention.

Testing of vacant lines or prospective subscriber lines is effectedremotely by connecting a test line permanently to one row of the matrixand selectively jumping that line, using the matrix jumper pins, todifferent vacant prospective subscriber pairs. The standard mechanizedloop tests (MLT) are applied to the line under test via the telephonenumber associated with the permanent test line.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and still further objects, features and advantages of thepresent invention will become apparent upon consideration of thefollowing detailed description of specific embodiments thereof,particularly when taken in conjunction with the accompanying drawingswherein like reference numerals in the various figures are utilized todesignate like components.

FIG. 1 is a front view in plan of a cross-connect matrix constructed inaccordance with the present invention.

FIG. 1a is a detailed plan view of a small portion of the matrix of FIG.1.

FIG. 2 is an exploded perspective view in partial section of a portionof the matrix of FIG. 1.

FIG. 3 is a schematic diagram of a matrix of the type illustrated inFIG. 1 subdivided to effect more efficient use of connections.

FIG. 4 is a view in elevation and partial section of a circuit jumperpin utilized to make connections between traces in the matrix of FIG. 1.

FIG. 5 is a diagrammatic sectional view in elevation of a portion of amatrix assembly of FIG. 1 illustrating the manner in which a circuitjumper pin and external connection posts engage the matrix assembly.

FIG. 6 is a view in perspective of a transport mechanism for effectingthree dimensional movement of a circuit jumper pin relative to thematrix assembly of FIG. 1.

FIG. 7 is a schematic diagram of the drive cable portion of thetransport assembly illustrated in FIG. 6.

FIG. 8 is a schematic illustration of the jumper pin picker platecarried by the transport mechanism of FIG. 6.

FIG. 9 is a schematic illustration of a solenoid-actuated brakingmechanism utilized with the transport assembly of FIG. 6, showing thebrake in both its released and engaged conditions.

FIG. 10 is a diagrammatic side view of the picker plate and itsactuating mechanism.

FIG. 11 is an electrical block diagram of the system for controlling thetransport mechanism and picker plate of FIG. 6.

FIG. 12 is a side view in partial section of the jumper pin pick andplace mechanism of the present invention shown with a jumper pin engagedand fully retracted.

FIG. 12a is a detailed side view in section of a portion of the pick andplace mechanism of FIG. 12.

FIG. 13 is a side view in section of the picker tip portion of themechanism of FIG. 12.

FIG. 13a is a detailed side view in section of a portion of the tipillustrated in FIG. 13.

FIG. 14 is a side view in partial section of the pick and placemechanism shown with a jumper pin being ejected for placement in thematrix.

FIG. 14a is a detailed side view in partial section of a portion of themechanism of FIG. 14.

FIG. 15 is a side view in partial section of the pick and placemechanism showing the jumper pin completely ejected from the picker tip.

FIG. 15a is a detailed side view in partial section of the picker tipand jumper pin portion of FIG. 15.

FIG. 16 is a side view in partial section of the pick and placemechanism showing a circuit jumper pin being engaged for removal fromthe matrix assembly.

FIG. 16a is a detailed side view in partial section of the picker tipand jumper pin portion of FIG. 16.

FIG. 17 is a schematic diagram of a telephone system utilizing utilizingthe matrix assembly of FIG. 1.

FIG. 18 is a schematic diagram of a portion of the circuit utilized inproviding the soft dial tone feature of the present invention.

FIG. 19 is another portion of the circuit utilized in conjunction withthe circuit portion illustrated in FIG. 18 to provide the soft dial tonefeature.

FIG. 20 is a schematic diagram of still another portion of the circuitutilized to provide the soft dial tone feature.

FIG. 21 is a schematic diagram of three separate matrix assembliesconnected together in providing the soft dial tone feature of thepresent invention.

FIG. 22 is a schematic diagram of the circuitry utilized to provideautomatic testing of unused cable pairs according to the presentinvention.

FIG. 23 is a schematic diagram of a circuit for providing additionalfeatures according to the present invention.

FIGS. 24a and 24 b are diagrammatic illustrations of circuit jumper pinsutilized in connection with the soft dial tone feature of the invention.

FIGS. 25-36 are flow charts representing programs for controllingvarious aspects of the system of the present invention.

FIG. 37 is a functional block diagram of the system of the presentinvention and illustrates the manner in which the cable pair and addresscan be obtained automatically for a soft dial tone caller requestingconnection for permanent service.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1, 1 a and 2 of the accompanying drawings, a matrixassembly 10 comprised as four stacked planar circuit boards 11, 13, 15and 17 of generally rectangular configuration. As viewed in FIG. 2,circuit board 11 is the first or top board and is designated herein asthe switch ring board. Circuit board 13 is the second board and isdesignated herein as the subscriber ring board. Circuit board 15 is thenext board in sequence and is designated herein as the switch tip board.Circuit board 17 is the bottom board and is designated herein as thesubscriber tip board. Designations such as “top” and “bottom” are usedherein for convenience only and are not to be construed as limiting theorientation of matrix assembly 10. An electrically insulative planarboard 12 is disposed in abutting relationship between circuit boards 11and 13 and is substantially coextensive in width and length with thoseboards. A similar insulative board 14 is disposed between circuit boards13 and 15, and another insulative board 16 is disposed between circuitboards 15 and 17. These circuit and insulative boards are compressedtogether by a plurality of rivets, or the like, to provide a compactmatrix assembly with each insulative board in abutting contact on eachof its surfaces with an adjacent circuit board.

Multiple matrix holes 20 are drilled or otherwise formed through theentire assembly, including all of the seven boards 11-17, in a directionperpendicular to the board surfaces. Matrix holes 20 may be formed inpatterns or groups as described in U.S. patent application Ser. No.08/111,770.

On the top (i.e., exposed) surface of switch ring circuit board 11 thereare multiple conductive switch ring traces 21 arranged linearly inspaced parallel relation. Switch ring traces 21 are typically platedonto the board surface by known techniques. Each trace or conductor 21extends along a respective row of matrix holes 20, whereby each row ofmatrix holes 20 in circuit board 11 has a respective trace 21.Corresponding switch ring traces 22 are plated onto the underside (i.e.,interior) surface of circuit board 11 in precise registry withrespective traces 21 on the opposite surface of board 11. Matrix holes20 extending through the board are conductively plated in a conventionalmanner to form female contacts 30 interconnecting their respectivetraces 21 and 22 at each hole 20. In addition to interconnecting traces21 and 22, female contacts 30 serve to permit interconnections betweendifferent circuit boards in the manner described below.

The subscriber ring circuit board 13 has multiple subscriber ring traces23 arranged linearly in parallel spaced relation on its top surface.Identical multiple subscriber ring traces 24 are defined in the bottomsurface of board 13 in precise registry with respective traces 23.Plated female contacts 30 are also provided in the matrix holes 20 ofboard 13. Traces 23 and 24 extend along respective columns of holes 20and are electrically connected by female contacts 30. Subscriber ringtraces 23 and 24 extend orthogonally relative to switch ring traces 21and 22 on circuit board 11.

On the switch tip circuit board 15 there are switch tip traces 25 and 26disposed at the top and bottom surfaces of the board, respectively, inan array identical to that for traces 21 and 22 of circuit board 11,that is, orthogonally to traces 23 and 24 of circuit board 13. On thesubscriber tip circuit board, opposite subscriber tip surface traces 27and 28 are arranged parallel to traces 23 and 24. It will beappreciated, therefor, that the switch traces on circuit boards 11 and15 are parallel to each other but orthogonal to the traces on circuitboards 13 and 17.

The traces and female contacts 30 on each board are insulated from thetraces and female contacts on successive circuit boards by the adjacentinsulation boards 12, 14 and 16 interposed between an abuttingsuccessive circuit boards. It will be appreciated, however, that anyswitch ring trace on circuit board 11, for example, can be electricallyconnected to any subscriber ring trace on circuit board 13 by providinga connection between female contacts of the two circuit boards at thematrix location where the two orthogonally related traces cross. Acircuit jumper pin 40 for effecting such connection is illustrated inFIG. 4 described in detail below.

In typical prior art switching matrices, each horizontal trace (e.g.,switch ring trace) and each vertical trace (e.g., subscriber ring trace)extend lengthwise entirely across their respective matrix boards. When ahorizontal trace is jumped or connected to any vertical trace, all ofthe other connector holes located on those traces becomes unavailablefor other connections. If, for purposes of facilitating understanding,we assume that the matrix has N horizontal traces and N vertical traces,it becomes apparent that only N connections can be made on the matrixeven though there are N² matrix holes. In the aforementioned U.S. patentapplication Ser. No. 08/111,770 there is disclosed a technique forexpanding the connection capacity of a matrix of given size by providingdiscontinuities in the traces to effectively provide sub-matrices of theoverall matrix. In that patent application, the preferred embodiment ofthis feature is disclosed as a gap or discontinuity line extendingdiagonally across the matrix to form two sub-matrices, effectivelyincreasing the connection point capacity of the overall matrix from N to2N−1. The technique may be expanded further by subdividing the matrix inother ways, for example into four sub-matrices as illustratedschematically in FIG. 3. In particular, matrix 33 is subdivided intofour equal capacity sub-matrices, occupying four respective quadrants,by horizontal and vertical discontinuity or gap lines. In the exemplarembodiment, matrix 33 is a square with ten horizontal rows of connectorholes and ten vertical columns of connector holes. The horizontaltraces, instead of extending entirely across the matrix, are interruptedbetween the fifth and sixth columns of holes. Similarly, the verticaltraces are interrupted between the fifth and sixth rows of holes. Thus,each horizontal trace is oriented coplanar and co-linear with, butelectrically isolated from, another trace in an adjacent sub-matrix. Theresult is four electrically isolated five-by-five sub-matrices occupyingthe same space as the overall ten-by-ten matrix. This arrangementpermits twenty connections to be made via the sub-matrices whereas onlyten connections can be made in the corresponding single matrix 33without providing the discontinuities in the traces. Importantly, thesub-matrices are formed by merely discontinuing the traces at thedesired isolation or dividing locations, not by physically positioningsub-matrices at different areas of the structure. Stated otherwise, thespace between successive adjacent vertical columns of holes 20 isconstant, whether the columns are in the same sub-matrix or in adjacentsub-matrices. Likewise, the spacing between successive adjacenthorizontal rows of connection holes 20 is the same whether the rows arein the same sub-matrix or in adjacent sub-matrices. As a consequence,the connection capacity of the matrix is doubled without requiring anyincrease in the physical size or space of the assembly.

Circuit jumper pin 40 is an elongated member having a grip 41 at itsproximal end and a tapered tip 43 at its distal end. Grip 41 isgenerally cylindrical with a predetermined diameter and a taperedproximal end. Pin 40 is made of an electrically insulative plasticmaterial that is somewhat flexible (i.e., bendable off its longitudinalaxis) in order to preclude breakage when the pin is subjected to bendingforces or off-axis longitudinal compression, but sufficiently rigid topermit the pin to be inserted through a set of aligned matrix holes 20in matrix assembly 10. In this respect the diameter of pin 40 is smallerthan the inner diameter of female contact 30. An annular stop flange 45extends radially from pin 40 at a location closer to the proximal endthan the distal end of the pin. Proximally of stop 45, the pin has ashort cylindrical section 44 with a diameter similar to the diameter ofgrip 41. Between section 44 and grip 41 there is a short reduceddiameter section 46 extending distally from grip 41 and terminating in adistally flaring frusto-conical section 47 that terminates at section44. Stop flange 45 has a diameter greater than that of hole 20 anddivides the pin into insertable and non-insertable length portions.Specifically, the insertable pin portion is located distally of stopflange 45, the depth of insertion into a matrix hole 20 being limited byabutment of flange 45 against the exposed top surface of circuit board11. The length of the insertable portion of pin 40 is such to permitdistal tip 43 to extend through and beyond the bottom circuit board 17when the pin is fully inserted into the matrix assembly (see FIG. 5).

The portion of fully inserted pin 40 extending between the femalecontacts 30 of circuit boards 11 and 13 is surrounded by a ring contactsleeve 47 of electrically conductive spring-like material. A similarlyconfigured tip contact sleeve 49 simultaneously extends between thefemale contacts 30 of circuit boards 15 and 17. When unstressed (i.e.,radially uncompressed), sleeves 47 and 49 have diameters slightly largerthan the inner diameter of female contacts 30. When pin 40 is fullyinserted into a matrix hole 20, sleeve 47 extends between and isradially compressed by aligned female contacts 30 on switch ring board11 and subscriber ring board 13. The radial compression of the resilientconductive sleeve assures positive electrical contact between the sleeveand the female contacts, thereby assuring connection between thecorresponding switch ring trace conductors 21, 22 and the subscriberring trace conductors 23, 24. Similar connection is made between theswitch tip trace conductors 25, 26 and the subscriber tip traceconductors 27, 28 by ring sleeve 49.

It will be appreciated that any pair of superposed switch ring traces21, 22 can be electrically connected to any superposed pair ofsubscriber ring traces 23, 24 by simply inserting a pin 40 into matrixholes 20 corresponding to the cross-over location of the traced pairsthat are to be connected. The tip traces for the same subscriber and thetip traces for the same switch line cross at the same matrix hole 20 sothat a complete tip and ring connection between the subscriber and theswitch can be made with a single circuit jumper pin 40. Pin 40 can bemanually or mechanically inserted and removed by grasping proximal grip41 and moving the pin axially in the desired direction. The tapereddistal end 43 of the pin facilitates insertion into holes 20. Byrendering the pin somewhat flexible, a slight axial misalignment of thepin during insertion will not hinder insertion and, more importantly,will not cause the pin to break due to axial bending stress.

Referring to FIG. 5, a diagrammatic cross-sectional illustration isprovided of matrix 10 showing a circuit jumper pin 40 inserted in amatrix hole 20 with the contact sleeves 47, 49 of the pininterconnecting trace conductors on different circuit boards.Specifically, contact sleeve 47 interconnects a contact 30 on circuitboard 11 with an aligned contact 30 on circuit board 13. Likewise,contact sleeve 49 interconnects a contact 30 on circuit board 15 with analigned contact 30 on circuit board 17.

Also illustrated diagrammatically in FIG. 5 is a plurality of wirewrapposts utilized to provide external connections for the matrix assembly.Post 51, representative of multiple such posts employed to provideexternal connections to trace conductors 27, 28 on circuit board 17, isan electrically conductive post of square transverse cross-sectionarranged to be longitudinally inserted, perpendicular to the matrix,into a plated female connector in a suitably provided square hole 50defined through circuit board 17. A plurality of such holes 50 are alsoshown in FIG. 1 wherein they are disposed in rows along the bottom ofthe matrix periphery. Wirewrap post 51 is engaged by the connector inhole 50 by means of a press or interference fit to assure properelectrical contact with trace conductors 27, 28 extending along circuitboard 17 beyond matrix holes 20. To assure positional rigidity of posts51 in hole 50, the juncture of the post and hole at the exposed surfaceof circuit board 17 may be soldered as shown or otherwise reinforced. Asubscriber tip wire 52 for a particular subscriber wire pair extendsfrom a cable, containing multiple subscriber wire pairs, to post 51wherein it is wrapped about post 51 in a manner assuring good electricalcontact.

Wirewrap post 53, exemplary of multiple such posts utilized to provideexternal connections to trace conductors 25, 26 on circuit board 15, isperpendicularly inserted into a plated female connector in a suitablyprovided hole defined through circuit board 15. Access to that hole inboard 15 is provided by a respective aligned hole 54 in circuit board17. A plurality of such holes 54 is shown in FIG. 1 wherein the holesare disposed in rows extending along the left side of the matrixperiphery. Holes 54 are not conductively plated to serve as conductors;instead, they merely provide access to plated holes in circuit board 15through similarly aligned access holes in the intervening insulativeboard 16. Post 53 is engaged in the plated hole in circuit board 15 by afriction or interference fit; solder, or the like, may be used at hole54 to provide positional rigidity for the inserted post. A line orswitch tip wire 55 is conductively wrapped about post 53 and is part ofa suitable cable carrying the switch tip wires.

At this point, it should be noted that posts 51 and 53 are shownadjacent one another in FIG. 5 only for purposes of convenience ofillustration. In actuality, the subscriber tip wirewrap post 51 isinserted into a hole 50 along the bottom edge of the matrix whereas theswitch tip post 53 is inserted into a hole 54 along the left edge of thematrix. Likewise, the wires 52, 55 for these posts are, in actuality,part of different cables carrying subscriber and switch wires,respectively.

In a similar manner, it can be seen in FIGS. 5 and 1 that wirewrap posts56 provide external connections to trace conductors 23, 24 on thesubscriber ring circuit board, and wirewrap posts 57 provide externalconnections to traces 21, 22 on the line switch ring circuit board 11.All posts 51, 53, 56 and 57 are inserted through holes from the exposedsurface of circuit board 17 which is the opposite exposed surface of thematrix from that into which the circuit jumper pins 40 are selectivelyinserted. Each wirewrap post makes electrical contact with traceconductors on only one circuit board, and the access holes for postsconnected to each circuit board are disposed in rows along respectiveedges of the matrix periphery.

During the manufacturing process of the matrix, the posts 51, 53, 56 and57 are inserted and terminated after all other steps in the matrixassembly process have been completed. The posts are shown as havingdifferent lengths depending upon their depth of insertion into thematrix assembly to the desired circuit board. It will be appreciated,however, that equal length posts can be utilized, thereby providing astaggered presentation of the exposed portions of the posts.

It will also be appreciated that all of the access holes, not merelyholes 50, may be plated at circuit board 17 to facilitate positionalstabilization of the posts by soldering to the plated holes. Under suchcircumstances, only holes 50 would also serve as electrical connectionsto trace conductors on circuit board 17.

A primary advantage of the wirewrap posts is that they can be unwrappedand re-wrapped as desired to provide a high degree of versatility forexternal connections to the matrix. For example, wires in the same cablecan be connected to different parts of the matrix. This would not bepossible with conventional plug and jack connectors since all cablewires must terminate at the same plug or jack.

The apparatus and the method for inserting and removing circuit jumperpins 40 relative to the matrix assembly is illustrated in FIGS. 6-16 towhich specific reference is now made. The mechanism for removal,transport and placement of the pin is unique in that it utilizes onlyone motor to control pin movement along three orthogonally related axes.Also unique is the technique for converting an imprecise cable drivemotion into an exact and positively locked position of the pin pickerrelative to any matrix hole 20. The drive assembly is mounted as a frameon the matrix assembly (the matrix assembly not being shown in FIG. 6 topreserve clarity and facilitate understanding) about the exposed surfaceof circuit board 11. Specifically, the drive assembly 60 includes anupper horizontal support 61, a lower horizontal support 62, a leftvertical support 63 and a right vertical support 64, all connected attheir ends to form a frame. It is to be understood that terms such asleft, right, upper, lower, horizontal and vertical are used herein tofacilitate relative description of the assembly parts for the particularorientation illustrated in FIG. 6. More particularly, the matrixassembly 20 and drive assembly 60 can be oriented in substantially anymanner without departing from the principles of the present invention.

Supports 61, 62, 63 and 64 define a rectangular or square frame aboutthe array of matrix holes 20. A horizontal transport tube 65 issupported at its ends by respective spaced flanges of upper supportmember 61. In this regard, the ends of horizontal transport tube 65 arethreaded and secured to respective flanges of support 61 by means ofnuts 67. A lower horizontal transport tube 66 is similarly supported byflanges of lower support member 62. Horizontal transport tubes 65, 66are parallel to one another and to the plane of the matrix panel, anddefine the X axis of motion referred to hereinbelow.

An upper block assembly 70 supports a pair of spool-shaped rollers 71,72 arranged to roll smoothly along the upper portion of the surface oftransport tube 65. Rollers 71 and 72 are arranged to freely rotate abouttheir respective support shafts 73 and 74 mounted on block 70 in aspaced mutually parallel orientation that is perpendicular to the matrixassembly 20. In this regard the rollers 71, 72 provide for smoothmovement of block 70 along the X axis within the limits imposed by theend flanges of support 61. The spool-type configuration of rollers 71,72 permits the rollers to engage the upper half of tube 65 in a mannerthat precludes the rollers and block 70 from moving off the X axis,thereby assuring only lineal movement along that axis.

A lower block assembly 75 is similar in most respects to upper block 70and supports a pair of similar spool-shaped rollers 76, 77 arranged toroll smoothly along the bottom half of the, lower support tube 66. Thisengagement by the upper and lower rollers of tubes 65 and 66 preventsthe picker unit (described below) from being tilted out of the X-Yplane.

Each of a pair of vertically-oriented tubes 80, 81 has its upper endsecured to upper block assembly 70 and its lower end secured to lowerblock assembly 75. This engagement provides for a rigid sub-assemblyformed by tubes 80, 81 and blocks 70, 75. A vertical transport carriage69 is provided with four spool-shaped rollers 82, 83, 84 and 85 arrangedto rotate about respective parallel support shafts mounted on carriage69 and oriented perpendicular to the matrix assembly. Rollers 82 and 83engage and freely roll along the inboard half of tube 80 that faces tube81. Likewise, rollers 84 and 85 engage and freely roll along the inboardhalf of tube 81 facing tube 80. Transport carriage 69 is therebyretained in a vertical plane defined by the parallel tubes 80 and 81.Likewise, the carriage is prevented from moving relative to these tubesin any direction other than vertical (i.e., along the Y dimension), andits Y-axis movement is limited by blocks 70, 75.

In order to assure that upper block 70 and lower block 75 movesimultaneously in the same direction, an alignment cable 87 is providedin conjunction with four alignment pulleys 88, 89, 90 and 91 mounted onrespective corners of the drive assembly frame. One end of the alignmentcable 87 is fixed to upper block 70 and extends to the left (as viewedin FIG. 6) and 180° around the upper left corner pulley 88. Alignmentcable 87 then extends horizontally along the frame top over to andaround upper right corner pulley 89 and turns 90° downward to and aroundthe lower right corner pulley 90. The cable turn is 90° about pulley 90and it then extends horizontally along the bottom of the frame to thelower left corner pulley 91. In extending between pulleys 90 and 91,cable 87 is clamped or otherwise affixed to lower lock 75 to assure thatthe lower block moves with cable 87. The cable then passes 90° aroundlower left corner pulley 91 and up to and around upper left cornerpulley 88 where it turns 90° and extends back across to the upper rightcorner pulley 89, turns 180° around that pulley and over to the upperblock 70 where the other end of the cable is secured. It will beappreciated that if the upper block moves in either direction along theX axis, it pulls alignment cable 87 in that direction and causes lowerblock 75 to move in the same direction.

A drive cable 100, as best illustrated in FIGS. 5 and 6, is wrapped afew times, in a windlass drive arrangement, about a drive capstan 101located near the upper left corner of the drive assembly frame. Drivecapstan 101 is rotatably driven by a step motor 102 mounted behind thecapstan on the upper lateral support 61. Drive cable 100 extendshorizontally in the X dimension from drive capstan 101 and engages anopto-shutter drive pulley 99 serving to measure drive cable movement.From the opto-shutter drive pulley 99 the cable extends in the Xdimension to an idler pulley 103 mounted on support 61 proximate theupper right corner of the frame. Drive cable 100 makes a 180° turn aboutidler pulley 103 and extends along the X dimension back to a leftmostidler pulley 104 mounted on upper block assembly 70. After turning 90°downward about pulley 104, each end of the drive cable is terminated ata cable tensioning device and extends in the Y dimension and then turns90° about a leftmost idler pulley 105 mounted on lower block 75, andthen extends to the right in the X dimension and turns 90° about arightmost idler pulley 106 also mounted on block 75. Drive cable 100then extends upwardly along the Y dimension to a lowermost idler pulley107 mounted on carriage 69 where the cable is turned 90° inward alongthe Z dimension onto a grooved edge of a picker plate drive pulley 108.Picker plate pulley 108 takes the form of a major portion of a circlelying in the Z plane, perpendicular to both the X and Y dimensions. Thepicker plate pulley, as best illustrated in FIG. 8, has a peripheryappropriately grooved to receive drive cable 100, and the drive cable isterminated in that groove at a point designated generally by thereference numeral 109. The drive cable 100 extends from point 109 in theZ direction to an uppermost idler pulley 110 mounted on carriage 69where the drive cable is turned 90° upward so that it then extends inthe Y dimension to a rightmost idler pulley 111 mounted on the upperblock 70. Pulley 111 turns the drive cable 90° to the left where itextends in the X direction back to drive capstan 101.

As best illustrated in FIGS. 9 and 6, horizontal transport tube 65 hasmultiple axially spaced slots 120 defined therein and extendingapproximately 75° circumferentially about the tube. In actuality thereare two series of such slots, each series being offset from the other byapproximately 90° on the tube circumference. The slots 120 in eachseries are disposed axially midway between the slots in the other seriesso that, from a longitudinal or axial prospective, each successive slotis offset 90° circumferentially from the preceding slot. The spacingbetween successive slots is precisely equal to the spacing betweensuccessive matrix holes 20 in the matrix assembly.

Two solenoids 121, 122 are mounted on the upper block assembly 70 andeach has a selectively extendable and retractable plunger with aprotruding pin. In FIG. 9, each solenoid 121, 122 is shown twice inorder to illustrate the energized and de-energized state of each atrespective slots 120; it will be understood that only one of eachsolenoid is provided. The plungers of the two solenoids areperpendicularly oriented relative to one another and positioned so thattheir pins are juxtaposed with respective offset series of slots 120 ontube 65. Thus, as upper block 70 moves in the X dimension relative totube 65, the plungers and pins of solenoids 121 and 122 are aligned withdifferent rows of slots. Importantly, the pins of plungers 121 and 122reside in the same plane perpendicular to tube 65 so that when theplunger and pin of one solenoid is aligned with a slot 120 in its seriesof slots, the plunger and pin of the other solenoid is disposedintermediate successive slots in its series. The pins extending from thesolenoid plungers have smaller diameters than the width of slots 120.Solenoids 121, 122 are of the type that retract their plungers when thesolenoid is energized but extend those plungers in response to a biasspring when the solenoid is de-energized. Accordingly, when bothsolenoids are energized, their plunger pins are retracted and clear tube65, thereby allowing unimpeded motion of the upper block 70 along the Xdirection. However, when either solenoid 121 or 122 are de-energized,its plunger pin rests upon the surface of lateral tube 65 and, underspring bias, is urged toward the tube and into a slot 120 aligned withthe plunger. Accordingly, the solenoids serve as brakes that areselectively actuable to prevent or permit movement of the upper block 70relative to tube 65. In a similar manner, a pair of solenoids 123 (onlyone being visible in FIG. 6) is mounted on carriage 69 to engage similarslots 120 defined in two 90°-separated series along the length ofvertical tube 81 and provide the same selective braking action for thecarriage along that tube. In actual operation, a solenoid iscontrollably de-energized just prior to completion of motion of block 70or carriage 69 so that the plunger can be extended to contact tube 65between slots 120. As the block or carriage continue to move, thede-energized solenoid plunger is forced into the next slot to stop themotion.

As viewed in FIGS. 8 and 10, also mounted on carriage 69 is a solenoid124 having a pin 125 movable in the X dimension to be selectivelyreceived in or withdrawn from a hole 126 defined in picker plate drivepulley 108. When solenoid 124 is de-energized, pin 125 engages hole 126and thereby prevents relative motion of the picker plate. When solenoid124 is de-energized, the picker plate drive pulley is able to rotate inthe Z dimension about an axis extending in the X direction. Inparticular, the drive cable 100, terminating as it does on rotatablepicker plate pulley 108, is able to rotate that pulley around theX-axis, and by virtue of the connecting rod 141, move the picker platein the Z direction when pin 125 is retracted from hole 126.

Movement of the picker assembly in any of the three dimensions X, Y andZ is therefore accomplished by energizing solenoids for the axis inwhich motion is desired and by energizing a single drive motor 102 todrive the capstan 101 and the drive cable 100. Specifically, the pickerassembly can be moved in the X dimension by energizing both solenoids121 and 122 to permit the upper block 70 to move freely relative to tube65; solenoids 123 and 124 remain de-energized so that Y and Z movementis prevented. Under these circumstances the portion of drive cable 100extending vertically down from idler pulley 104 to idler pulley 105,over to idler pulley 106, around pulleys 107, 108 and 110 and up topulley 111 is stationary because of the braking. The drive system maythus be viewed as a movable horizontal loop of drive cable 100 extendingbetween pulleys 101 and 103, with the remainder of the drive pathsuspended therefrom and movable horizontally therewith. Likewise, ifsolenoids 123 are both energized, carriage 69 is able to move verticallyunder the control of step motor 102 as long as solenoids 121, 122 and124 are de-energized. Under these circumstances the horizontal drivecable loop about pulleys 101 and 103 cannot move the positionally lockedpulleys 104, 105, 106 and 111 horizontally but can pull pulley 110 (andcarriage 69) up or pull pulley 107 (and carriage 69) down, depending onthe direction of rotation of motor 102. Z dimension movement,accordingly, is accomplished by energizing solenoid 124 while solenoids121, 122 and 123 are deenergized. Under these circumstances pulleys 104,105, 106, 107, 110 and 111 are locked in place and the only movableelement is picker pulley 108 to which both ends of cable 100 are fixed.Movement of the picker pulley is strictly rotational and produces arelatively small range of movement of the cable. A greater range ofmovement, if required, could be achieved by increasing the circumferenceof drive pulley 108 so that the length of cable engaging that pulleywould similarly increase. Importantly, this system only permits motionin one direction at a time.

The opto-shutter drive pulley 99, when rotated by drive cable 100,rotates a shutter in a conventional manner which sequentially turns anopto-coupler on and off to create electrical pulses that may be countedby the system processor. The pulses that are counted have a directrelationship to linear movement of the cable and the picker that isdriven by the cable. Thus, if motor 102 malfunctions, or if cable 100slips on capstan 101, the processor receives fewer pulses and initiatesa corrective action or alarm.

Initial positioning registration may be accomplished by means ofswitches (not shown) when the vertical assembly is positioned to theextreme leftmost position and when the carriage 69 is positioned at theextreme lowermost position. Specifically, carriage 69 may be movedlaterally to the left until a limit switch is sensed. Solenoids 121 and122 may then be de-energized and carriage 69 moved laterally to theright until one of the associated solenoid plunger pins drops into aslot on lateral tube 65, thereby arresting further lateral movement. Thepicker can then be positioned over the bottom row of holes in the matrixpanel by moving the carriage 69 downward until the lower vertical limitswitch is operated and sensed. With solenoids 123 de-energized, thecarriage can be moved upward until a plunger pin of one of solenoids 123extends into a slot 120 in the vertical tube, thereby preventing anyfurther movement. The picker is thus positioned over the lowermost rowof matrix holes in the matrix panel.

It is to be noted that for precise registration of the picker over theindividual matrix holes, the flange nuts 67 engaging the tubes 65, 66,80 and 81 (as viewed in FIG. 6) may be loosened, allowing axial movementof the tubes so that the slots 120 can be positioned as necessary foralignment with matrix holes 20. Once the tubes are properly positioned,the nuts 67 are tightened to prevent further tube movement.

Control over movement of the drive assembly is derived from a remotelocation, typically at a central telephone system office. A generalizedblock diagram of equipment located at the remote location of the drivesystem and permitting such remote control is illustrated in FIG. 11 towhich specific reference is now made. Control signals from a telephonesystem central office are received by a modem 129 having an interface130 arranged to format the signals and distribute them via amicroprocessor bus 131 to microprocessor 132. Bus 131 provides signalcommunication between the microprocessor and all of the controlledequipment and data processing circuits at the remote station.Microprocessor 132 controls operation of the equipment at the remotestation, including the step motor 102, the horizontal brake solenoids121, 122, the vertical brake solenoids 123 and the picker brake solenoid124. A non-volatile read/write random access memory (RAM) 133 isprovided to store the status (i.e., whether or not occupied) of thevarious matrix locations, and the hole locations of the various circuitjumper pins 40. A read only memory (ROM) 134 stores the operating systemprogram and application program to operate the microprocessor. Avolatile RAM 135 serves the function of transient working storage.

The step motor 102 is controlled by a stepper motor translator 127 whichin turn is controlled by a stepper indexer 128. Translator 127 andindexer 128 are commercially available components utilized in aconventional manner to control stepping motors. Translator 127, forexample, may be a model NEAT SDN7, manufactured by New EnglandAffiliated Technologies, while indexer 128 may be a model INDEXER LPT(using line printer controller) manufactured by Ability SystemsCorporation. In response to control signals received from microprocessor132 via bus 131, stepper indexer 128 applies step signals to thetranslator 127. The translator responds by applying appropriate controlsignals to motor 102 to positionally step the motor and move drive cable100. Upon the picker mechanism reaching the desired location in eachdirection, the appropriate brake solenoids are actuated/de-actuated toeffect a change in picker movement direction.

Referring to FIG. 10 of the accompanying drawings, the picker platedrive pulley 108 is shown mechanically linked to a picker plate 140 bymeans of a reciprocating action connecting arm 141. Specifically, uponrotation of the picker plate drive pulley 108, connecting arm 141 pushesor pulls the picker plate 140 in the Z direction (i.e., perpendicular tothe matrix panel 20). The picker plate 140 carries a picker tip 143capable of grabbing and releasing a jumper pin 40 in the mannerdescribed below. The details of the picker tip 143 are illustrated inFIGS. 12-16 as described in the following paragraphs.

It will be appreciated that the concept of employing a single drivecable and single motor has numerous advantages over using a separatedrive arrangement for each axis of movement. Moreover, the drivearrangement described above is particularly advantageous for providingindividual motion along two or three orthogonally related axes. However,the single cable and motor arrangement, combined with selective brakingalong all but one axis at a time, may be employed to control movementalong other than orthogonally related axes. For example, a polarco-ordinate system could be used whereby a pivotable tube, slotted inthe manner of support tube 65, is pivotable through 360°. At its distalend the tube supports a block arranged to ride along an annular tubethat is similarly slotted. A carriage supporting, for example, thepicker described above, is arranged to ride along the rotatable tube.Solenoids on the carriage have plungers of the type described toselectively engage the slots along the rotating tube to brake andpositionally define the carriage position along the rotatable tube.Solenoids on the block are selectively energized to brake andpositionally define the angular position of the rotatable tube relativeto the annular tube. The picker plate and pulley are the same asdescribed. A single motor drives a single drive cable engaged by pulleyson the block, carriage and picker to move the picker only along theunbraked axis. The controlling microprocessor is programmed to providepolar co-ordinates for picker movement and destination, rather thanrectilinear coordinates as in the system described above.

As illustrated in FIGS. 12, 12 a, 13 and 13 a, the picker tip assemblyincludes a solenoid 138 having an armature 137 with an armatureextension 136 projecting from the proximal end of the armature. Ahelical spring 148 biases the armature extension 136 to its proximallyprojected position when the armature is deenergized and has been pushedback by virtue of the picker tip 143 descending over a pin. A pickerhead 139 is secured to the distal end of the solenoid 138 and includes atip 143 capable of carrying a circuit jumper pin 40. A microswitch 145mounted on the carriage 69 is actuated when the armature extension 136is proximally retracted (i.e., the solenoid is de-energized and a pin isin the picker) and is deactuated when the solenoid is energized.

The picker tip 143 includes a hollow cylindrical section for receivingthe proximal end of circuit jumper pin 40. An annular protuberance ornub 147 extends radially inward in the hollow cylinder to reside insection 46 of jumper pin 40 when the jumper pin is fully engaged,thereby preventing jumper pin 40 from being inadvertently pulled fromtip 143.

The proximal end of the solenoid armature 137 has a slightly enlargeddiameter adapted to abut an annular cammed portion 146 of the interiorof the hollow cylindrical picker tip 143 upon actuation of the solenoid.

Referring to FIGS. 14 and 14a, when the solenoid is energized, thedistal end thereof is projected distally causing the enlarged portion ofthe armature to forcefully bear against tip cam 146. Distally of the tipcam 146, the picker tip 143 is longitudinally slit to define fourspreadable leaves or arms which open in response to the forward forcefulbearing of the enlarged armature portion against tip cam 146. Theopening of these leaves or arms removes the holding barks 147 from thepin 40 and allows further distal movement of the armature 137 to therebypermit complete ejection of pin 40 from picker tip 143 and into a matrixhole of the panel 10. Upon this distal movement of the energizedarmature, as best illustrated in FIGS. 15 and 15a, the pin 40 iscompletely ejected and the proximal end 136 of the armature clearsswitch 145 which deactuates to indicate that there is no pin in thepicker. Note that when jumper pin 40 has been fully ejected, theenlarged diameter portion of the distal end of the armature has clearedthe tip cam 146, thereby permitting the leaves of the picker tip 143 toclose.

Referring to FIGS. 16 and 16a, the initial portion of a pin pickingoperation is illustrated showing the circuit jumper pin 40 beingforcefully urged against the distal end of the de-energized solenoidarmature 137, forcing the enlarged portion of the solenoid armatureproximally in forceful engagement with the tip cam 146 to spread theleaves of the picker tip 143 and permit entrance of the circuit jumperpin 40 into the picker tip 143 until it is openly engaged byprotuberance 147 (as better illustrated in FIG. 12a). The pushing of thearmature proximally actuates switch 145 to indicate that a pin is in thepicker tip.

The matrix assembly described above may be used at a location remotefrom a telephone system central office to selectively connectsubscribers to central office lines. This mode of utilization has beendescribed above and in U.S. patent application Ser. No. 08/111,770. Itis also possible to utilize the matrix assembly at the central office toeliminate the requirement for manually connecting tip and ring pairsbetween the mainframe and the central office switching equipment. Inparticular, in a typical telephone system, individual two wire linesfrom the customer's home or business are installed using various typesof facilities, such as paired wires, buried cable, underground cable,etc. These smaller wire groups and cables are formed into larger cablesthat ultimately terminate at a telephone company mainframe at a centraloffice. The mainframe has the necessary protective devices to prevent orreduce damage from lightning and other hostile environmental sources.

From the protected side of the mainframe, two wire jumpers for eachcustomer, representing tip and ring, are manually installed andconnected to the central office equipment line termination. Thesecentral office line terminations are permanently connected by cables tothe central office switching machine, and are the connecting linkbetween the physical facility and the software in the stored programcontrol portion of the switching machine. Each central office linetermination is associated with a respective telephone number in thestored program residing in the switching machine.

When a customer places a call, the receiver is lifted and a scanner inthe switching machine peripheral equipment recognizes the “off-hook”condition and provides dial tone. The switching machine recognizes thedigits dialed and translates them to the proper trunks that send thecall to the desired location based on the dialed number.

For an incoming call the telephone numbers and codes dialed by thedistance party are translated into the proper office equipmenttermination which is connected via a two wire jumper at the mainframe tothe cable pair that is connected to the called customer's facility. Whenthis connection is made, the switching machine applies ringing tones andcurrent and, when the customer answers, conversation can begin.

The above explanation of a conventional system is presented in order topoint out the facilities and components involved in system operation.When the customer disconnects and moves away from the dwelling orbusiness unit, all of the facilities are left connected from the unit tothe central office equipment. The expense and inefficiency of thismethod of operation is described hereinabove. The present inventionprovides methods and apparatus for solving these problems. One aspect ofthe invention, in this regard, involves inserting matrix assembly 10 inseries with the customer's line between the protected side of the maindistribution frame and the central office line equipment. This is astrategic point in the facility circuit, thereby eliminating thenecessity of manually making the two wire cross-connection between themainframe and the central office line termination. Referringspecifically to FIG. 17, matrix assembly 10 is inserted in series withthe customer lines 153 at a strategic point between the mainframe 154and the terminating equipment at the central office 156. This permitsall cross-connections between the mainframe 154 and the central officeline terminating equipment 156 to be made automatically from a remotelocation, thereby eliminating the labor and the material expense ofplacing and removing cross-connections manually. The subscribers 151 andtheir individual two-wire lines 152 form part of larger cables 153.

While this solves many problems for telephone companies such as the timeand labor of manually making cross-connections, as well as the abilityto make these connections at night during off hours from a remotelocation, the other problems described hereinabove are solved by otheraspects of the invention as described below.

Specifically referring to FIGS. 18 and 19, there is presented aschematic representation of the “soft dial tone” (SDT) option circuitboard associated with a portion of a cross-connection matrix panel 10 ofthe type described above. The SDT option circuit board is typicallyinstalled on the back of the matrix panel. The rightmost one-third ofFIG. 18 represents a portion of the matrix panel itself. Four groups ofeight crosses (“X”) are shown on lines Ln1, Ln2, Ln3 and Ln4. Thesecrosses represent connecting pins fully inserted into the matrix holes20 at these locations. In other words, for example, there are eightjumper pins 40 inserted into the matrix panel at line Ln1 which is sodesignated because it is in the first line position on the matrix. Notethat until the connecting pins are inserted, line Ln1 has no significantcorrelation with any particular cable pair except that cable pair CP#1happens to be a cable pair terminated on matrix line Ln1 when theconnecting pin is inserted.

At the upper right portion of FIG. 18 there are illustrated cable pairsCP#1 through CP#63 terminated at the top of the matrix panel. Each ofthese cable pairs extend from the central office to the customer aspreviously described and are commonly referred to as “the subscriberloop”. Any one of these subscriber loops can be connected to anyhorizontal line Ln1 through Ln75 by the insertion of a jumper pin 40 asdescribed above. Thus, for the disclosed preferred embodiment, there areseventy five horizontal lines per quadrant of the matrix, and theselines are numbered Ln1 through Ln75, respectively.

It is important to note that the insertion of eight circuit jumper pins40 on line Ln1 serves to connect one-half of each of the correspondingeight cable pairs CP#1 through CP#8 together on line Ln1. These pinshave a contact sleeve on the ring portion of the jumper pin only (i.e.,not on the tip portion of the jumper pin).

A second group of crosses is shown on line Ln2 and represents eightother subscriber loops CP#9 through CP#16 connected together on lineLn2. The same is true for the third and fourth groups of eight crossesdesignating connections of lines Ln3 and Ln4, respectively to cablepairs CP#17 through CP#24 and cable pairs CP#25 through CP#32,respectively. This pattern is repeated to provide eight groupings ofeight cable pairs. In FIG. 18, however, there are only thirty twosubscriber loops shown connected to four horizontal rows on the matrixpanel.

It is to be noted that only the ring side of the cable pair circuits areconsidered in FIG. 18. This is accomplished by only connecting the ringside (i.e., the battery side of the loop) to the SDT circuit board.There is a wired connection 160 between the ring side of the horizontalline Ln1 and the SDT circuit board at r1. The tip side of all horizontallines Ln1 through Ln8 are not shown connected in FIG. 18; instead, FIG.19 is concerned with the tip side of the circuits. The circuitryeffectively splits the tip and ring sides of all cable pairs, puttingthe ring sides under control of the SDT circuit board of FIG. 18 and thetip sides under control of the SDT circuit board of FIG. 19. It is to benoted that, in FIG. 19, circuit jumper pins designated by crosses areinserted in line Ln1 to tie together cable pairs CP#1, CP#9, CP#17,CP#25, etc.; that is, the first cable pairs from each grouping of eightare tied together. These circuit jumper pins have a contact sleeve onlyon the tip portion of the pin. Likewise, on line Ln2, cable pairs CP#2,CP#10, CP#18, etc. are tied together; these are the second cable pairsof each grouping of eight. This pattern is continued through all of theother pair groupings and is done in order to provide a means of uniquelydetermining which cable pair (of the sixty two total pairs) goesoff-hook in a request for service.

At the upper central portion of FIG. 18, reference numeral 161represents the connection to central office battery. Eight sets of dualwinding coils Ldr1 through Ldr8 are connected to this central officebattery lead 161. These dual winding coils serve as loop currentdetectors. A respective set of contacts 162(1) through 162(8) isassociated with respective loop current detectors Ldr1 through Ldr8.When current flows through any one of these loop current detectors, thecontact 162 associated with that current detector closes. Referring toFIG. 19, it is observed that the same arrangement is provided for thetip side of the circuit. The tip side detectors LDt1 through LDt8 haverespective contacts 164(1) through 164(8).

Referring back to FIG. 18, a logic ground connected to the normally openside of the contact associated with loop current detectors Ldr1 throughLdr8. The common terminal of these contacts is connected to diodes ineight sets of diode matrices 165(1) through 165(8). Each diode matrix165 is associated with a respective relay coil Kr1 through Kr8, and thediode anodes is each matrix are connected together and to one side ofthe associated relay coil. The cathodes of each of the eight diodes ineach matrix 165 are connected to a respective common terminal or contact162(1) through 162(8) of a respective relay Ldr1 through Ldr8. The samearrangement is provided in FIG. 19 for the tip side of the SDT line. Inthis case the relays are numbered Kt1 through Kt8 and the respectivediode matrices are designated by reference numerals 166(1) through166(8).

In describing operation of the system, it is assumed that a potentialcustomer moves into a vacant dwelling or office unit that has cable pairCP#17 connected thereto. When the customer requests telephone service,the receiver is lifted off-hook, and the switch contacts in thetelephone unit close to complete the loop circuit. In FIG. 18, cablepair CP#17 has the first cross (i.e., “X”) on line Ln3 (for Ring side).In FIG. 19, cable pair CP#17 has the third cross on line Ln1 (for Tipside).

From the central office battery connector 161 (FIG. 18), current flowsthrough loop current detector Ldr3, the normally closed contacts Kr3A ofrelay Kr3, and connection 160 to the matrix panel. At the matrix panelthe current flows through the cross-connection (“X”) at cable pair CP#17and line Ln3, up through the matrix cable pair CP#17, out through thesubscriber loop and through the telephone unit switch hook. The currentpath returns to the tip side of the cable pair and re-enters the matrix(FIG. 19) on cable pair CP#17 at line Ln1. Current then flows throughcable pair CP#17 to the tip cross connection (“X” at cable pair CP#17and line Ln1, then through the normally closed contacts of relay contactKt1 a through the tip side loop detector relay Ldt1 and back to centraloffice ground. This path is a complete circuit for the dial tonerequest. In this condition there are two and only two loop detectorrelays actuated, namely relay Ldr3 on the ring side and Ldt1 on the tipside.

When loop detector Ldr3 is actuated, a circuit path is completed fromlogic ground through the closed contact 162(3) of loop current detectorLdr3, through the diode associated with relays Kr1, Kr2, Kr4-Kr8, andthrough the windings of these relays to +48V. The current through thispath actuates all relays Kr1 through Kr8 except for relay Kr3. Normallyclosed contacts Kr1 a, Kr2 a and Kr4 a through Kr8 a open as a result oftheir respective relays being actuated, but contact Kr3 a remainsclosed. The actuated relays Kr1, Kr2 and Kr4 through Kr8 open thecircuits for all telephone lines in the groups of eight except for thoseon line Ln3; this is because contacts Kr3 a remain closed.

When current flows in cable pair CP#17, relay coil Ldt1 (FIG. 19) isenergized and closes a circuit path for logic ground through contact164(1) associated with relay Ldt1. Voltage is present at the windings ofevery relay Kt2 through Kt8 which are thereby energized through theirconnections to +48V. Relay Kt1 is not actuated, however. This opensrelay contacts Kt2 a through Kt8 a, thereby disconnecting the tip sideof the matrix, except for connections to line Ln1. Line Ln3 (FIG. 18)and line Ln1 (FIG. 19) are the only lines having access to centraloffice battery and ground under these conditions. In other words, cablepairs connected to Ln3 are the only cable pairs provided with centraloffice battery on the ring side, and cable pairs connected to line Ln1are the only cable pairs connected to central office ground on the tipside. Accordingly, only that cable pair connected to both lines Ln3 andLn9 can draw loop current.

The system must identify which cable pair has gone off hook. In thisregard, it is noted that all of the Kr and Kt relays except Kr3 and Kt1are actuated. This specifies unique column and row signals available forthe system to determine the exact cable pair that is presently off-hook.The row identifications are indicated at the left hand side of FIG. 18,while the column identifications are indicated at the left hand side ofFIG. 19. What is sent back to the control unit is the row number threeand column number one indication. This is the unique signal applicableonly to cable pair CP#17 going off-hook. A unique circuit path is thusprovided between central office battery and central office ground, andis connected between the r and t pair of lines designated Q1SDT shown inthe upper left corner of FIG. 20. In this regard, the “Q1” portion ofthe signal designates a particular quadrant, namely quadrant one, of thematrix panel. Accordingly, the Q1SDT signal is the soft dial tone signalfor quadrant one. That signal actuates loop detector relay 170 to closerelay contact 171 and place −GNDout (i.e., logic ground) on the OPTO-1line.

The previously described operations are all completed automatically bythe SDT hardware in less than twenty milliseconds. The systemperiodically polls the OPTO-1 line to determine if a party on quadrantone seeks soft dial tone service. In a system utilizing plural matrixpanels, the system determines which panel has brought up the OPTO-1signal. The system thus knows which panel and quadrant is requestingsoft dial tone service. Ground and forty-eight volts are then providedto read the matrix row and column codes identifying the soft dial tonerequester as indicated by the energized Ldt and Ldr relays.Specifically, referring again to FIGS. 18 and 19, the −Q1SEL signal(i.e., the select signal for quadrant one) provides a ground on rows onethrough eight (FIG. 18) and columns one through eight (FIG. 19) toindicate which cable pair is requesting service. This information isalso required to determine the circuit jumper pins that must be moved toeffect service on the requestor's line without additional lines beingpartially “bridged” to that line. In this regard, the term “bridged” isnot intended to mean parallel connection of lines in the conventionalsense of both tip and ring of two or more lines being connectedtogether. Rather, in the example described, the tip of cable pair CP#17is connected to the tip of cable pairs CP#1, CP#9, CP#25, CP#33, etc.,and the ring of cable pair CP#17 is connected to the ring of cable pairsCP#18 through CP#24.

Referring again to FIG. 20, the −Q1SEL signal also energizes relay K1.This serves to transfer central office battery from contact K1 b, and totransfer central office ground from contact K1 a, to soft dial tone ringand tip, respectively, on the Soft Dial Tone Buss. As a result, thecustomer on cable pair CP#17 is provided with a connection to the SoftDial Tone Buss.

For an explanation of how all systems and individual panels of amultiple panel system are connected to the central office to receivesoft dial tone, reference is made to FIG. 21 wherein three controlsystems for three cross connection systems are shown. System one isshown as including four panels XP#1 through XP#4 and typically wouldserve one thousand lines; system two is similarly configured with fourpanels; and system three has three panels to typically serve sevenhundred and fifty lines. Each system is connected by two dedicated linesto a telephone central office. Depending upon the volume of calls, theremay be up to eight of these dedicated lines. The dedicated lines arephysically the same as any other telephone line except that theircentral office terminations are treated for soft dial tone in thesoftware of the central office switching unit to prevent any user fromcalling any number except the emergency 911 and the number of thetelephone business office.

The two soft dial tone lines illustrated in FIG. 21 are designated911-Line#1 and 911-Line#2. Control units shown in FIG. 21 are designatedCU#1, CU#2 and CU#3; that is each of the three systems has its owncontrol unit. Each control unit has its own relay switches 172 which,when actuated, have the capability of connecting the calling line to oneof the dedicated central office soft dial tone lines. Each of thecontrol units CU#1 through CU#3 has the capability of determining, byvirtue of line detectors, whether or not there is a party connected to a911 line and, by virtue of the line detectors in the other controlunits, whether or not the other systems have a party connected to a 911line.

Referring still to FIG. 21, for purposes of the present description itis assumed that control unit CU#2 has connected one of its controlledcalling cable pairs to 911-Line#2; accordingly, current through theloop, as previously described, flows through line detector relay 173 ofcontrol unit CU#2. When the relay contact 174 associated with relay 173is thusly closed, it places ground (a low logic level) on the −LN2BSY(i.e., line 2 busy). This low logic level is available to all othercontrol units to indicate that the 911-Line#2 signal line is busy andnot available for connection to other telephone lines. Thus, the threeseparate multi-matrix systems share two 911 lines, and each systemcontrol unit is capable of determining whether or not these lines areavailable or busy.

At the lower left corner of FIG. 21 there is a signal designated #1SDTrepresenting the soft dial tone buss for system number one. This buss ispresent on every panel of system number one. Since the control unit CU#1has selected only a particular panel (i.e., the panel having the firstcustomer calling in on a cable pair), the #1SDT signal is provided onlyfrom the selected panel, and is applied to both switches SW#1 and SW#2of switch pair 172 for system one. This configuration is duplicated insystem two and system three (and in any additional systems).

Control unit CU#1 interrogates both the 911-Line#1 and 911-Line#2 bymeans of line detection relays 175 and 173, respectively. Thus, if911-line#2 is available for use, a relay is actuated to close SD#2 ofswitch pair 172 so that the #1SDT buss can be connected through to the911-line#2. The customer utilizing cable pair CP#17 is thusly connecteddirectly to a hard-wired circuit at the telephone central officeswitching machine. This circuit, as described above, is treated for softdial tone.

By energizing relay 173 connected to the 911-line#2 line, the controlunit CU#1 for system number one has notified all other control units forthe other systems that the 911-line#2 signal line is busy and notavailable for connection.

It must be remembered, from the description of the circuitry in FIGS. 18and 19, that the above-described connection is not a “good circuit”because fourteen other circuits are still partially bridged to cablepair CP#17 even though those circuits are not themselves in the off-hookstate. This is similar to party line operation. The capacitance of theselines, depending upon their lengths and degree of line balance, tend tohave some degrading effect on the high frequency components of voicesignals on cable pair CP#17. On the other hand, the bridged lines havelittle effect on central office supervision (i.e., the ability of thecentral office switching machine to recognize off-hook signals, dialpulses, etc.) and on dual tone multi-frequency (DTMF) signals.Therefore, the switch accepts the call and begins call progress towardthe business office or 911 control, depending upon which number thecustomer dials.

All of the circuit operations described above are initiated when anoff-hook condition exists on cable pair CP#17 and all of the operationsare rapid and automatic. By the time the customer places the receiver tohis/her ear, the customer is connected via the soft dial tone line inthe manner described and hears conventional central office dial tone.With this type of connection, the call may be completed and conversationmay take place. It will, however, sound “tinny” if very long customerloops are utilized. Since the soft dial tone customer is not paying forregular telephone service, this condition would be satisfactory for mostsituations. However, in order to eliminate the possibility of serviceproblems, the present invention provides for removing all bridgedconnections to the line being connected to the central office dial tonefacility. Specifically, the system removes the bridged lines andprovides a standard high quality telephone circuit during the period oftime between the customer goes off-hook and the call is answered. Thisis achieved in the manner described in the immediately followingparagraphs.

Referring to FIG. 21, the telephone circuit from the 911-line#2 line,through the loop detector relay 173 to the #1SDT buss and back to thecircuitry in FIG. 20, has been completed in the above-described example.The circuit extends through respective contacts K1 a and K1 b of loopdetector relay K1 in FIG. 20 to provide the two Q1STD signals for thecircuitry in FIGS. 18 and 19.

In FIG. 19, the STD tip signal passes through the line detector relayLdt1 and closed relay contact Kt1 a to terminal t₁ where it is connectedby means of connection 169 to the matrix illustrated at the right handside of FIG. 19. At the matrix the signal passes through the circuitjumper pin in the matrix hole at the seventeenth position to thecustomer's hook switch and on to the customer's ring side of the line.From there the signal returns, in FIG. 18, on line Ln3 through theconnecting pin in the seventeenth position. From there the signalprogresses from the matrix through the cross connection to the soft dialtone circuit board at terminal r₃ via connection 160. At the soft dialtone circuit board the signal passes through relay contact Kr3 a, loopdetector Ldr3, and back to the SDT ring side to complete the circuit.

The lines that are still bridged in parallel with cable pair CP#17 areseven circuits on line Ln3 (FIG. 18) and seven circuits on Ln1 (FIG.19). In order to remove the bridged inactive subscribers from the line,the unique capabilities of the system pick and place mechanism describedabove are utilized. Specifically, the calling line (i.e., cable pairCP#17) is transferred to a direct line at the central office by means ofthe matrix. This is achieved while the call is in progress and while allof the other bridged lines are being removed, and it is achieved withoutinterrupting the call. The only indication to the customer that anythingis happening on the line is a cessation of any line hum, and thetransmission suddenly becomes clearer. To achieve this, and referring toFIG. 21, it is noted that for the above-described example, the buss911-line#2 is present on panel XP#1 of system number one. It is alsopresent on each quadrant of the other panels XP#2, XP#3 and XP#4 of thatsystem. Still assuming that the calling line CP#17 is in quadrant one ofpanel one, upon completion of the path as described above, the softwarein control unit CU#1 commands the pick and place mechanism to remove apin from a spare pin location on the matrix and place it (see FIG. 19)at the seventeenth column on line Ln9. This ties line Ln9 directly to911-line#2 through the line detector relay 173 (FIG. 21). The foregoingprovides the connection and keeps a busy condition on the 911-line#2line.

Under the described conditions there exists a parallel connection forcable pair CP#17. Specifically, the original connection on the soft dialtone buss is still present. Since that connection is the link to theparallel telephone lines bridged to cable pair CP#17, it is necessary torelease that connection in order to remove all lines bridged to cablepair CP#17 and thereby provide a perfect telephone line. An importantaspect of the present invention is that, since it is a parallelconnection, the soft dial tone connection can be removed with no adverseeffect while the call is in progress to 911 or to the telephone businessoffice.

Referring to FIG. 18 to illustrate how the soft dial tone connection andbridged lines are released, as soon as the second connection is made (asdescribed above) the pick and place mechanism is commanded to remove thecircuit jumper pin at line Ln3 and place it in an unused or parkposition on the matrix. This has the effect of removing seven of thefourteen cable pairs that were bridged to line Ln9. In other words, oncethe direct connection to the soft dial tone telephone line has beenmade, the temporary connection is removed to remove the bridged cablepairs. When this is completed the pick and place mechanism is commandedto move to line Ln1 and remove the pin that is at column seventeen andplace it in a non-used or park position on the matrix. This has theeffect of removing the other seven lines that were still partiallybridged or paralleled with line Ln9. At this time no other party is onthe telephone company 911 circuit except the party connected to cablepair CP#17. The calling customer is thus provided with a circuit havinga quality as good as that provided for any paying customer connected tothe system.

Removal of the −Q1SEL signal can now be effected to restore all contactsto their original state in preparation for the next request for service.Pulling connector pins from column seventeen on line Ln3 of FIG. 18 andline Ln1 in FIG. 19 prevents any loop current from flowing through loopdetector relays Ldr3 and Ldt1. This deactivates all relays Kr1 throughKr8 (FIG. 18) and Kt1 through Kt8 (FIG. 19) and places them in a readystate for the next request for service. The system has thus made adirect connection to a normal telephone line for cable pair CP#17, andthe panel and quadrant have been released and made ready to serve thenext soft dial tone requestor.

It should be understood that, for purposes of facilitating understandingthe drawings, only two telephone company 911 soft dial tone lines areshown in the drawings. In this implementation up to eight lines may beutilized for this purpose.

It should also be noted that, for purposes of facilitatingunderstanding, only three systems are illustrated in FIG. 21, and thesesystems, in the described example, service a total of two thousand sevenhundred and fifty lines. Depending upon the needs of the telephonecompany and the anticipated usage, the system can be separatelyconfigured so that all customers can be served in one system, and thatany particular matrix system can be configured in any given size andshape to serve the needs of the telephone company.

The foregoing description relates to the insertion of the matrix systemof the present invention at a strategic point in a telephone systemcentral office so as to permit remote and automatic control of theplacing, moving and removing of cross connections between a cable pairfrom the premises of a customer and a central office line termination.Also described is a method and apparatus for deploying the matrix systemin a manner to relieve telephone companies from the requirement ofleaving expensive central office line terminations connected to everynon-working cable pair, i.e., dedicated inside plant. Further, theforegoing describes a method of immediately identifying a particularcustomer from among thousands that may be requesting service fromnon-subscriber cable pairs.

The foregoing description is based upon the presence in the centraloffice switching machine of software capable of denying access toconnected but non-paying stations to all numbers except 911 and thetelephone business office.

A further feature of the invention, as illustrated diagrammatically inFIG. 37, is the ability to collect and store a prospective customer'sfacility and dwelling or business data at a remote matrix system andthen transmit the data to a video screen at the service representative'sposition. This is effected in response to a call from a customerapplying for service. As described above, this feature greatly expandsand magnifies the capabilities of the telephone system and, therefore,the value to the telephone company of the present invention.

When a customer applying for service lifts the receiver 250 to place thecall to the business office, the remote matrix system 251 recognizes theoff-hook condition and identifies the calling cable pair used by thecustomer in the manner disclosed above in relation to the soft dial tonefeature of the invention. The remote matrix 251 then automaticallyrequests the other facility data previously stored at the administrativeworkstation 252 for the specific address associated with that cablepair. The caller is automatically connected via data-over-voice (DOV)modem 253 and begins dialing the business office. The facility data forthe calling cable pair and the customer's address are then down-loadedvia a four-wire modem 254 to the remote matrix system and stored. Whenthe telephone 257 rings at the service representative's position 256 andis answered, the off-hook at the service representative's position isseen by data-over-voice (DOV) modem 253 as a “go ahead” and all facilitydata is transmitted to the service representative's video screen.

With the exact facility data for the address of the calling customervisible on the screen, conventional customer contact takes place. Whenall credit and contact information is taken from the customer, theservice representative calls the administrative workstation 252,down-loads all facility and address information, and instructs theoperator to establish permanent service. With the customer on-line, theline is tested for satisfactory service, and permanent service is thenestablished.

A further feature of the invention relates to providing means fortesting vacant (i.e., non-working) cable pairs remotely. In the priorart, there is no capability of testing non-working telephone linesutilizing central office mechanized loop testing equipment. This isbecause all automatic test equipment makes connections to the telephoneline via a telephone number. If a line does not have a telephone numberassigned to it, the only way to test the line is to have a techniciantravel to the mainframe, install a “test shoe” which connects a voltmeter circuit to the cable pair, and perform the test manually. This isso time consuming as to render the procedure economically unfeasible.The present invention solves this problem in the manner described below.

Referring to FIG. 22, a regular telephone line 185 for testing isconnected to a horizontal line on matrix panel XP#1 of the presentinvention. The system administration center is aware, bypre-programming, of the X-coordinate line to which 185 is connected.Cable pairs for that quadrant are terminated on the vertical orY-coordinate columns, and the system is aware of which cable pairs arevacant and to which columns they are connected. When it is desired totest a vacant cable pair, no action is needed by technicians. Rather, atthe remote administration center 187, the administration center managerorders the pick and place mechanism to make the connection between acable pair in the matrix column to be tested and the test line 185. Thismakes the selected vacant cable pair temporarily the same as a workingtelephone line using the number assigned to the system test line. Themechanized loop testing equipment 188 is then utilized to conduct alltests normally done on a working cable pair.

The system thus provides telephone companies with a test feature notpresently available. The technique is also advantageous in centraloffices not equipped with special devices and test capabilities.

As noted above, the security of central offices in telephone systems isof great concern. Even small, unattended offices contain millions ofdollars worth of equipment, test gear, records and building investment.Labor costs have created the need for operating these offices in anunattended mode with technicians being dispatched thereto from a centrallocation only when necessary. There are numerous different work groupsrequiring entry into these offices. To provide all members of thesegroups with a key to the office doors is tantamount to leaving the dooropen. Presently, multiple different schemes for protecting keys areutilized by telephone companies. The present invention providestelephone companies with an economical and positive way of assuring thesecurity of these buildings. This feature is also illustrated in FIG.22.

Specifically, electric door locks 189 are installed on all buildingscontrolled by the remote administration center 187. The system controlunit CU#1 provides access to two sets of relay contacts via a screwterminals. The door lock solenoid is connected to a central officebattery, the other side of the solenoid to a central office door lockline 191 which, in turn, is connected to one screw terminal 192 on theback of the control unit. Central office ground is connected to theother screw terminal 193. A standard “ring down” telephone is installedbetween the doors of all buildings to the administration control center.A “ring down” line is a line that rings automatically in a remotelocation when the receiver is lifted at the other end; i.e., no dialingis necessary. When an employee desires to enter a telephone building,he/she lifts the receiver on the ring-down telephone mounted in aweatherproof housing at the entry point. The telephone automaticallyrings in the administration center 187 via the special line 194. Theattendant at the administration center answers and asks the employee forhis/her password. All employees authorized to enter the particularbuilding are assigned respective passwords associated with their names.When the correct password is given, the administration control centercommands the matrix system to activate the relay to complete the circuitfrom the central office battery (i.e., plus 48 volts) through thewinding of the door lock solenoid 189 to central office ground. Thiscauses the door to be unlocked. The control unit CU#1 is programmed toleave the door relay closed for an arbitrary time interval (e.g.,approximately fifteen seconds and then de-activate it. This locks thedoor circuit until the next authorized entry. The central office controlsoftware automatically maintains a record of the date, time and name ofthe person who entered the facility.

Although the security mechanism described above is not technicallysophisticated, it is economical, sure-acting, and far superior to thepresent key system currently in use. Although numerous technicallysophisticated systems can perform the security function, they tend to bequite expensive, thereby explaining why telephone companies have chosennot to install security systems. The present invention, in its ultimatesimplicity, meets these needs of a telephone company.

The system disclosed herein in connection with FIG. 17 eliminates theneed for telephone companies to maintain excessive investment in centraloffice line equipment and telephone numbers in order to operate in aDedicated Inside Plant (DIP) mode. A further object of the invention isto enable telephone companies to eliminate the investment in outsideplant cable pairs necessary for them to operate in a dedicated outsideplant (DOP) mode. It will be recalled that FIG. 17 illustrates a systemwherein the matrix assembly of the present invention is installedbetween the central office mainframe 154 and the central office lineterminating equipment 156 in order to eliminate the labor of placing andremoving two-wire cross-connections manually. Referring now to FIG. 23,a serving area interface 204 of the type typically utilized by telephonecompanies is essentially a manual cross-connection point. It functionsexactly like a mainframe cross-connection process in the central office.In the typical outside plant equipment, the feeder cable pairs 195 fromthe central office mainframe to the interface are connected to terminalstrips inside the interface. Technicians typically place a two-wirecross-connection between these terminal strips in order to connect apair of wires from the central office to the customer. The purpose ofhaving a serving area interface 204 is to make concentrated feeder pairsavailable to a wide number of distribution cable pairs that are spreadover a large geographical area. It would greatly reduce the flexibilityof the investment in feeder cable pairs to have them connected directlyto the distribution cable pairs in all cases.

Just as the matrix assembly of the present invention is installedbetween the cable pairs and the central office line termination as shownin FIG. 17, the matrix assembly of the present invention can be insertedin the connections between the distribution cables and the centraloffice feeder cables in a system shown in FIG. 23. Specifically, this isdone at the interface 204 where the SDT circuit board 196 is installedand the feeder pairs 200 are cut as indicated at 195. The feeder pairsare also disconnected from the interface 204 and connected instead tothe horizontal traces of the matrix panel 197. The distribution pairs206 are removed from the interface 204 and terminated on the verticaltraces of matrix 197. This effectively provides soft dial tone servicefor as few as two hundred fifty subscriber pairs using onlyfour-to-eight feeder pair. This configuration is expandable to up tofive thousand lines per system.

A test line 185, the 911-line#1 and 911-line#2 lines, are connected tothe matrix unit 197.

In the system as thusly configured, the matrix assembly functions underthe control of the remote administration center just as if it were inthe central office. Therefore, the explanation as to how the systemprovides soft dial tone and reconnection services for several thousandcable pairs using only a few dedicated 911 lines is the same aspreviously described and set forth above in connection with the centralunit.

The circuit jumper pin 40 described hereinabove in relation to FIG. 4 iseffective to accomplish connections at a matrix assembly in the mannerdescribed. That pin is also useful to effect connections for the softdial tone operation described above in relation to FIGS. 18-20. However,use of circuit jumper pin 40 requires a plurality of individual pickermovements in the connection/disconnection process, resulting in theprocess consuming more time than is desirable for certain applications.For example, if the system calls for a specific connection to be made,the picker unit must be translated along the X and Y axes successivelyto reach a spare pin location, then moved along the Z axis to firstengage and then remove the spare pin, then translated along the X and Yaxes successively to the matrix hole at which a connection is to bemade, and then moved along the Z axis to first insert the pin and thenwithdraw from the inserted pin. The total time required for theprocedure depends on the distances traversed by the picker, buttypically require on the order of fifteen or more seconds. This may begenerally acceptable when making a permanent connection for a newsubscriber since the subscriber is not on the line waiting for theconnection to be made. On the other hand, during the soft dial toneprocedure the caller lifts the handset and expects to immediately heardial tone. If the soft dial tone bus is currently in use for the periodof time to remove two soft dial tone pins,” the absence of dial tone forso long a time may result in the party replacing the handset andassuming that the dial tone is not available. In order to reduce theconnection time, therefore, a modified circuit jumper pin configurationhas been provided and is illustrated in FIG. 24 to which specificreference is now made.

FIGS. 24a and 24 b diagrammatically illustrate two modified circuitjumper pins 211 and 212. Pins 211 and 212 are identical except for thelocations of their respective contact sleeves. Both pins are shownengaged in respective matrix holes 221 and 222 in a matrix assembly 220.That matrix assembly may be the same matrix described above as matrix20, but the illustrations in FIGS. 24a and 24 b focus on the soft dialtone signal trace portion of the matrix. Four trace conductors 215, 216,217 and 218 are shown in the drawing and are configured similar to thetrace conductors illustrated in FIG. 3, each being located in arespective plane parallel to the planes of the other conductors.Preferably, the trace conductors are each of the dual trace type,meaning that each trace conductor is actually two juxtaposed conductivetraces disposed on opposite sides of a circuit board. The matrix holesare conductively plated at the signal traces as described above topermit electrical connections to be made in the manner described.

Each circuit jumper pin 211, 212 is an elongated cylindrical memberhaving a grip 231 at its proximal end and a conical distal tip 233 witha radially enlarged annular flange at its proximal end. Grip 231 isgenerally cylindrical with a predetermined diameter and a taperedproximal end. The pin is made of an electrically insulative materialand, over the contact portion of its length, has a diameter smaller thanthe inner diameter of the plated contacts in matrix holes 221, 222. Anannular stop flange 235 extends radially from the pin at a locationcloser to the proximal end than the distal end of the pin. Proximally ofstop 235, the pin has a short cylindrical section 234 with a diametersimilar to the diameter of grip 231. Between section 234 and grip 231there is a reduced diameter section 236 of generally hourglassconfiguration. Stop flange 235 and the flange on distal tip 233 havediameters greater than that of holes 221, 222 and establish theinsertable length portion of the pin. Specifically, the insertable pinportion is located between stop flange 235 and the flange of tip 233,the two flanges serving to trap the pin in its matrix hole. Each pinthus has a fully inserted position and a fully retracted position in itsrespective matrix hole. The fully inserted position for pin 212 isillustrated in FIG. 24a along with the fully retracted position of pin211. The pin positions are reversed in FIG. 24b.

The distalmost part of the insertable portion of pin 212 is surroundedby a tip contact sleeve 239 of electrically conductive spring-likematerial. A similarly configured ring contact sleeve 237 surrounds theproximalmost part of the insertable portion of pin 211. Contact sleeves237 and 239 may take the same form as sleeves 47 and 49 described abovein relation to FIG. 4. When unstressed (i.e., radially uncompressed),sleeves 237 and 239 have diameters slightly larger than the innerdiameter of the female contacts in the matrix holes. When pin 212 isfully inserted into its matrix hole 222 (FIG. 24b), its sleeve 239extends distally partially beyond the matrix and makes no contactbetween trace conductor 218. When pin 212 is in its fully retractedposition (FIG. 24b), its contact sleeve 239 is radially compressed byaligned female contacts on trace conductors 217 and 218. This radialcompression of the resilient conductive sleeve assures positiveelectrical contact between the sleeve and the female contacts, therebyassuring connection between the corresponding traces 217 and 218. Whenpin 211 is fully inserted into its respective hole 222, contact sleeve237 is radially compressed by aligned female contacts on traceconductors 215 and 216. On the other hand, when in its fully retractedposition, pin 211 is positioned with its sleeve 237 partially withdrawnfrom its matrix hole 222, and no cross-connection is made.

It will be appreciated that pin 212 effects cross-connections when fullyretracted, whereas pin 211 effects a cross-connection when fullyinserted. In order for each pin to be changed from a connection tonon-connection condition, or vice versa, it need only be pushed orpulled within its permanent matrix hole. The pushing or pulling may beachieved by hand or with the same mechanism described above in relationto FIGS. 6-16; however, the picker need only be translated to one X-Ycoordinate position since there is no need to first move to the positionof a spare pin and then translate the pin to the matrix hole at which aconnection is to be made.

It will be further appreciated that the trapped circuit jumper pinsillustrated in FIGS. 24a and 24 b permit considerable time saving duringoperation, but this time saving is achieved only at the expense ofrequiring each matrix hole to permanently retain its own pin. Theinitial cost of pins is therefore a tradeoff against speed of operation.Thus, although the trapped pins are clearly suitable for soft dial toneoperation where operating speed is important but relatively few pins arerequired, this may not be the case for establishing full customerservice where many hundreds of pins would be required but operatingspeed is not critical.

In describing the operation and effect of opto-shutter drive pulley 99in connection with FIGS. 6 and 7, mention is made that malfunctions ofmotor 102, or slippage of cable 100 on drive capstan 101, results in acorrective action or alarm. Specifically, the microprocessor 132 (FIG.11) is described as receiving conflicting pulse counts from theopto-shutter counter that is driven by pulley 99 and from the count ofthe step motor steps expected for picker movement being controlled. Aflow chart for this portion of the software, as stored in microprocessor132, is illustrated in FIG. 25 to which specific reference is now made.

The picker is commanded to move the number of steps (corresponding tomatrix holes) necessary to reach the desired pin/connection location. Asthe picker moves, a running count of discrete motor steps is maintained.Likewise, the opto-shutter counter registers counts for respectivediscrete units of length of cable 100 passing over pulley 99. Thesediscrete length units correspond to the spacing between successivematrix holes. In response to the total of motor steps, the opto-shuttercount modified by a multiplier, is compared to the total motor stepcount. If the counts are equal, picker movement is considered to becorrect; if not, an error count is incremented and the picker is movedto a first matrix hole position serving as a starting reference. If theincremented error count is less than two, the system begins again tomove the picker to the commanded location. If a count discrepancy occursagain, the error count will equal two and, accordingly, an errorindication is displayed.

The system described above is controlled by a microprocessor, typicallya personal computer, located at the telephone system central office. Thesoftware used in the computer for effecting system operation isillustrated in flow chart form in FIGS. 26-35. It will be appreciatedthat much of the system operation is only broadly illustrated in thoseflow charts; it is only the particular features of the present inventionthat are represented in greater detail in the flow charts and describedbelow.

Referring to FIG. 26, the start routine for the system goes throughinitial setup and initialization before requesting the user to enter apassword. Upon proper entry and verification of an acceptable password,a remote site screen is displayed.

The options made available to the system operator via the remote sitescreen are illustrated in FIG. 27. The election of different operatingmodes may be via a menu selection or window selection process, orpossibly a combination of the two. Of the twelve options shown in FIG.27, only the utility option and the dial option are described in detailherein.

The remote site utility option, when selected, follows the procedureillustrated in FIG. 28. Specifically, the operator is asked to selectfrom seven options, including backup database, restore database, formatdiskette, reports, edit database, configure soft dial tone, and useraccounts. The only one of these options described in detail herein isthe configure soft dial tone option which is illustrated in detail inFIG. 29.

Upon election of the configure soft dial tone option, the operator isfirst asked to confirm the election of that option. Upon suchconfirmation being entered into the system, the configure SDT screenappears and gives the operator the option of performing a number ofdifferent operations. For example, the operator can set a particularmatrix panel in a multiple panel system for reconfiguration, or he/shecan set the particular quadrant on the selected panel for soft dial toneconfiguration. The on/off option can be elected to permit the operatorto have the soft dial tone feature available or not on a particularpanel. The configuration option for the selected panel and quadrantpermits soft dial tone features to be established thereon. Exiting fromthe routine returns the system to the remote site screen illustratedfunctionally in FIG. 27.

Another option made available on the remote site screen is the dialoption which permits the operator to call a particular remote sitehaving a cross-connect matrix system installed thereat. The dial routineis illustrated in detail in FIG. 30 to which specific reference is nowmade. Upon a command to dial a particular site being initiated, thesystem determines whether or not a database exists for that site and, ifnot, a database is generated. The files for the site are then opened andthe actual dialing process begins. If no connection is made, an errorindication is provided and the system returns back to the remote sitescreen. If connection is effected a determination is made as to whetheror not the dial back enable feature is “on” for the remote site. Thisfeature is a security feature permitting the remote location to dialback to the central office. If the feature is activated, the centraloffice sends a command to the remote location to dial back the centraloffice, and then hangs up the modem. When the dial back call arrives, orif the dial back enable feature is not activated, the data base isloaded into the system and the main screen for the remote site isdisplayed.

The main screen options are illustrated in FIG. 31. The only options ofspecific interest to the present invention are the test bus option andthe connect/disconnect options. The test bus option is illustrated indetail in FIG. 32 to which specific reference is now made. The operatoris given the option of identifying a cable pair of a line circuit to betested. Upon election of a cable pair by entry of the appropriate cablepair number, the system determines whether or not a test pin is insertedto connect that cable pair to the test bus. If it is, the system returnsto the main screen; if it is not, a test pin is moved to that location,the subscriber database is appropriately updated, and the system returnsto the main screen. Testing may be performed automatically on theselected cable pair as desired. A similar process is applied for testinga line circuit; that is, the system determines whether or not a test pinis connected in the appropriate location for that line circuit and, ifnot, a test pin is so moved. When the operator wishes to disconnect thetest bus from a particular location, the disconnect option is selected,the cable pair or line circuit number is obtained, and a determinationis made as to whether or not the test pin is at the location for thatnumber. If not, the process returns to the main screen display; if so,the test pin is moved to a spare pin position.

Referring to FIG. 33, if the connect option is selected at the mainscreen, the operator is permitted to select the cable pair and linecircuit to be interconnected. The operator is then asked to confirm theconnection. If the particular juncture, (i.e., matrix hole 20)corresponding to the selected cable pair and line circuit is shown inthe database for the matrix as being occupied, an error indication isflashed on the screen and the system returns to the main screen display.If the particular matrix location is available, a spare pin is moved bythe pick and place mechanism to the selected line circuit position, thematrix spare pin location database and matrix hole database are updated,and the system returns to the main screen display.

Referring to FIG. 34, if the disconnect option is selected from the mainscreen, the operator need only designate the cable pair to bedisconnected and confirm the disconnection since the line circuit towhich that cable pair is connected is identified in the matrix database.If the database indicates that the selected cable pair has no connectionon the matrix, an error is indicated and the system returns to the mainscreen display. On the other hand, if the matrix database indicates thatthere is a circuit jumper pin in place for the cable pair to bedisconnected, that pin is moved to a spare pin location, and thedatabases are appropriately updated. The system then returns to the mainscreen display.

The response of the system to a request for soft dial tone service isillustrated in the flow chart of FIG. 35. In particular, the systemcontinuously poles the potential soft dial tone cable pairs to see ifany of those cable pairs has gone off-hook. When such cable pair goesoff-hook, a determination is made as to whether or not a special SDTline circuit is available. If so, the internal soft dial tone bus isconnected to the first available special SDT circuit by means of therelay circuitry described in relation to FIGS. 18, 19 and 20. Theappropriate panel and quadrant of the requesting cable pair isidentified and the cable pair is connected to the internal SDT bus aspreviously described. The row and column numbers from the actuatedrelays identify the cable pair, which can then be connected to the SDTline circuit already connected to the SDT bus by using a circuit jumperpin (this results in the parallel connection described hereinabove). Thespecial tip and ring pins are then removed to remove the parallelconnection of the cable pair to the SDT bus. The SDT bus is thenconnected from the special SDT line circuit that was previouslyselected, thereby rendering the system free for the next request forsoft dial tone.

Disconnection of soft dial tone service is illustrated in FIG. 36.Specifically, the system looks to determine whether or not any cablepairs are connected to the special SDT line circuit by a connection pin.If so, a determination is made as to whether or not the cable pairconnected to the special SDT circuit is still off-hook. When that cablepair is no longer off-hook, it is disconnected from the special SDT linecircuit by pulling the connection pin illustrated in FIG. 24. The cablepair is reconnected to the SDT bus by returning the special tip and ringpins illustrated in FIG. 24 to their appropriate positions.

The present invention, as described above, makes available a method andapparatus for inserting a cross-connection matrix into a strategic pointin a telephone central office in a manner to position the matrix toremotely and automatically control the placing, moving and removing ofcross-connections between a cable pair to the customer's premises andthe central office line termination. In addition, the system provides amethod and apparatus for deploying a cross-connection matrix in a mannerto relieve telephone companies from the requirement of leaving arelatively expensive central office line termination connected to everynon-working cable pair in order to have dedicated inside plant.

The invention as described above also provides a method and apparatusfor immediately identifying a single customer from among thousands ofcustomers that are requesting service from a non-working cable pair. Inaddition, a method and apparatus are disclosed for setting up a parallelpath through the matrix of the present invention in order to improve thequality of a circuit utilized for soft dial tone. Means are disclosedfor enabling the system to remove the initial path from the parallelconnection without interrupting progress of the call.

The system further makes available a method and apparatus for taking anon-working line from a group of sixteen such lines and connecting theselected line to a normal central office telephone line while leaving noconnections to the other pairs that were originally bridged andparallel.

The system as disclosed herein also has the capability of automaticallyphysically transferring a calling line to a standard telephone line, andachieving this from a remote location with no interruption of a call inprogress.

Having described preferred embodiments of a new and improvedcross-connection method and apparatus constructed and operated inaccordance with the present invention, it is believed that othermodifications, variations and changes will be suggested to personsskilled in the art in view of the teachings set forth herein.Accordingly, it is to be understood that all such variations,modifications and changes are believed to fall within the scope of thepresent invention as defined by the appended claims.

What is claimed is:
 1. The method of increasing the capacity of theswitching matrix of the type having matrix holes for receiving jumperpins to join juxtaposed conductors at different depths of a matrixstructure, wherein the matrix holes are arranged in columns and rows,all adjacent columns being substantially equally spaced, all adjacentrows being substantially equally spaced, said method comprising thesteps of: interrupting the continuity of said conductors at the samelocation at each of said depths to thereby define the electricallyinsulated sub-matrices with adjacent matrix hole columns of adjacentsub-matrices having the same spacing as adjacent columns within eachsub-matrix, and with adjacent matrix hole rows of adjacent sub-matriceshaving the same spacing as adjacent rows within each sub-matrix.
 2. Aninterconnection matrix system comprising: a first circuit board having afirst surface with a first array of multiple electrical conductorsthereon, said first circuit board having multiple matrix holes definedtherethrough and through said electrical conductors at predeterminedlocations along said conductors in said first array, said matrix holesbeing disposed in a rectangular grid of columns and rows; a secondcircuit board having a first surface with a second array of multipleelectrical conductors thereon, said second circuit board having multiplematrix holes defined therethrough and through said electrical conductorsin said second array at predetermined locations along said conductors insaid second array, wherein the matrix holes in said first circuit boardare concentrically aligned with corresponding matrix holes in saidsecond circuit board, said matrix holes of said second circuit boardbeing disposed in said rectangular grid; wherein each of said arrays issub-divided into a plurality of electrically unconnected sub-arrays inwhich the conductors in each sub-array are co-planar, wherein eachconductor in each sub-array is electrically isolated from butco-linearly aligned with a respective conductor in another sub-array,wherein each sub-array on the first circuit board is aligned injuxtaposition with a corresponding sub-array on the second circuitboard, and wherein the aligned sub-arrays define a respective pluralityof electrically isolated sub-matrices; wherein said sub-matrices areseparated by a plane extending perpendicular to said arrays anddiagonally to said conductors; wherein the spacing in said rectangulargrid between adjacent columns being the same for all adjacent columnsincluding adjacent columns in the same sub-matrix and adjacent columnsin adjacent sub-matrices, and the spacing between adjacent rows beingthe same for adjacent rows including adjacent rows in the samesub-matrix and adjacent rows in adjacent sub-matrices.
 3. The matrixsystem of claim 2 wherein said sub-matrices are four in number, eachsub-matrix having a generally rectangular configuration wherein itscolumns of matrix holes are longitudinally aligned with respectivecolumns of one adjacent sub-matrix, and wherein its rows of matrix holesare longitudinally aligned with respective rows of another adjacentsub-matrix.
 4. The matrix system of claim 2 wherein said sub-matricesare four in number and are generally rectangular.
 5. The matrix systemof claim 2 further comprising: access holes disposed within said firstand second circuit boards; and wire wrapped posts for providing externalconnections to said sub-matrices, said wire wrapped posts being insertedinto said access holes to establish said external connections.
 6. Thematrix system of claim 5 wherein each of said wire wrapped postsselectively establish external connections to any of said sub-matrices.7. The matrix system of claim 5 wherein said matrix system is connectedto others of said matrix systems and each of said wire wrapped postsselectively establish external connections to any of said connectedmatrix systems.
 8. The matrix system of claim 2 wherein cable pairs andcentral office lines are connected to said matrix system and acontinuous portion of said matrix holes form a global bus for connectingsaid matrix system via a connector to others of said matrix systems forestablishing a connection between cable pairs and central office linesresiding on different matrix systems.
 9. An interconnection matrixsystem comprising: a first circuit board having a first surface with afirst array of multiple electrical conductors thereon, said firstcircuit board having multiple matrix holes defined therethrough andthrough said electrical conductors at predetermined locations along saidconductors in said first array; a second circuit board having a firstsurface with a second array of multiple electrical conductors thereon,said second circuit board having multiple matrix holes definedtherethrough and through said electrical conductors in said second arrayat predetermined locations along said conductors in said second array,wherein the matrix holes in said first circuit board are concentricallyaligned with corresponding matrix holes in said second circuit board; aplurality of jumper pins permanently disposed within said aligned matrixholes, each of said jumper pins comprising an elongated cylindrical bodyhaving a grip and a stop flange toward a proximal end and a conicaldistal tip with a radially enlarged flange at the proximal end of saidtip, said jumper pins being in either an inserted or retracted positionwithin said matrix holes; wherein each of said arrays is sub-dividedinto a plurality of electrically unconnected sub-arrays in which theconductors in each sub-array are co-planar, wherein each conductor ineach sub-array is electrically isolated from but co-linearly alignedwith a respective conductor in another sub-array, wherein each sub-arrayon the first circuit board is aligned in juxtaposition with acorresponding sub-array on the second circuit board, and wherein thealigned sub-arrays define a respective plurality of electricallyisolated sub-matrices.
 10. The matrix system of claim 9 furthercomprising a pin positioning means for manipulating said jumper pins tosaid inserted position to establish a connection between conductors ofsaid first and second circuit boards and manipulating said jumper pinsto said retracted position to terminate a connection between conductorsof said first and second circuit boards.
 11. A method of transporting ajumper pin, by means of a pin picking and placing mechanism, to and fromindividual junction locations in a switching matrix, said methodcomprising the steps of: (a) moving said mechanism selectively in eitherof two opposite directions along a first path by means of a drive motorand translating said mechanism along a first support extending alongsaid first path; (b) moving said mechanism selectively in either of twoopposite directions along a second path by means of said drive motor andtranslating said mechanism along a second support extending along saidsecond path, wherein said first and second paths are disposed in atransport plane parallel to said matrix; (c) moving said mechanism ineither of two selective opposite directions along a third path disposedperpendicular to said transport plane by means of said drive motor androtating said mechanism about an axis oriented parallel to saidtransport plane; (d) limiting movement of said mechanism to only aselectable one of said first, second and third paths at a time byselectively inhibiting movement of said mechanism along the other two ofsaid paths, wherein said drive motor is the only source ofmotion-producing force for said drive mechanism along said first, secondand third paths, and motion along only the selected path is effected bypositively blocking movement of the mechanism along the two non-selectedpaths, and wherein step (d) further includes: (d.1) interengaging saidmechanism with said first support to inhibit movement of said mechanismalong said first path; (d.2) interengaging said mechanism with saidsecond support to inhibit movement of said mechanism along said secondpath; and (d.3) blocking rotation of said mechanism to inhibit movementof said mechanism along said third path; wherein steps (a), (b) and (d)further include translating a single drive cable by means of said drivemotor, and passing said drive cable over a series of idler pulleyssecured to said mechanism and defining a cable path; and (e) displayingan error indication in response to a detection of a slippage of saidsingle drive cable or a malfunction of said drive motor.
 12. The methodof claim 11 wherein one of said series of idler pulleys drives anopto-shutter counter, and wherein said detection of a slippage includes:determining the number of steps of said drive motor duringtransportation of said pin; determining the number of discrete lengthunits of said drive cable passing over said one pulley by saidopto-shutter counter; comparing the number of drive motor steps to thenumber of discrete length units; and indicating an error in response tothe comparison yielding a non-matching result.